As filed with the Securities and Exchange Commission on August 8, 1997

                                                     Registration No. 333-

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                               UNILAB CORPORATION
             (Exact name of Registrant as specified in its charter)

               Delaware                                95-4415490


       (State or jurisdiction of                    (I.R.S. Employer
    incorporation or organization)                    Identification No.)


                              18448 Oxnard Street
                            Tarzana, California 91356
                                 (818) 996-7300

              (Address,  including zip code, and telephone  number,
   including area code, of Registrant's  principal executive offices)



              UNILAB CORPORATION 1997 DIRECTORS STOCK PURCHASE PLAN
                 UNILAB CORPORATION NON-QUALIFIED STOCK OPTIONS
                   UNILAB CORPORATION RESTRICTED COMMON STOCK

                           (Full Title of the Plans)

                               Mark L. Bibi, Esq.
                          Vice President, Secretary and
                                 General Counsel
                               Unilab Corporation
                              401 Hackensack Avenue
                                    9th Floor
                          Hackensack, New Jersey 07601
                                 (201) 525-1000
                     (Name, address, including zip code, and
          telephone number, including area code, of agent for service)

<TABLE>
                         CALCULATION OF REGISTRATION FEE
<CAPTION>
         Title of Securities            Amount to be    Proposed Maximum    Proposed Maximum         Amount of
           to be Registered              Registered      Offering Price    Aggregate Offering     Registration Fee
                                                          Per Share(1)          Price(1)
<S>                                     <C>                  <C>          <C>                    <C>
Common Stock, par value $.01 per        4,004,261(2)         $1.375       $5,505,859             $1668
   share

</TABLE>
(1)  Estimated  solely  for the  purpose of  calculating  the  registration  fee
     pursuant to Rule 457(c) and rule 457(h)  promulgated  under the  Securities
     Act of 1933, as amended (the "Securities  Act"),  based upon the average of
     the high and low prices per share of the Common Stock (such  average  being
     $1.375) as reported on The American Stock Exchange on August 4, 1997.

(2)  Represents  (i)  25,000  shares  issuable  upon  the  exercise  of  certain
     nonqualified  options  granted to an  employee;  (ii)  2,979,261  shares of
     restricted  stock issued to certain  employees,  consultants and directors;
     and  (iii)  1,000,000   shares  issuable  in  connection  with  The  Unilab
     Corporation 1997 Directors Stock Purchase Plan. This Registration Statement
     also relates to such indeterminate number of additional  shares of Common
     Stock as may be issuable as a result of stock splits, stock dividends or
     similar transactions.
<PAGE>
                               UNILAB CORPORATION
 
                 FORM S-8 CROSS REFERENCE SHEET SHOWING LOCATION
                  OF INFORMATION REQUIRED BY PART I OF FORM S-3

     Form S-3 Item Number                        Location/Heading in Prospectus

1.   Forepart of Registration Statement and      Cover Page
     Outside Front Cover Page of Prospectus

2.   Inside Front and Outside Back Cover         Available Information;
     Pages of Prospectus                         Incorporation of Certain
                                                 Information by Reference

3.   Summary Information, Risk Factors           Not Applicable
     and Ratio of Earnings to Fixed Charges

4.   Use of Proceeds                             Use of Proceeds

5.   Determination of Offering Price             Not Applicable

6.   Dilution                                    Not Applicable

7.   Selling Security Holders                    Selling Stockholders

8.   Plan of Distribution                        Plan of Distribution

9.   Description of Securities                   Not Applicable
     to be Registered

10.  Interests of Named Experts and Counsel      Experts; Legal Matters

11.  Material Changes                            Not Applicable

12.  Incorporation of Certain Information        Incorporation of Certain
     by Reference                                Information by Reference

13.  Disclosure of Commission Position on        Indemnification of Officers
     Indemnification for Securities Act          and Directors
     Liabilities

<PAGE>

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.   Incorporation of Documents by Reference.

     The following  documents  previously filed with the Securities and Exchange
Commission (the "Commission") by Unilab Corporation (the "Registrant")  pursuant
to the  Securities  Act of 1933,  as amended (the "1933 Act") or the  Securities
Exchange Act of 1934, as amended (the "1934 Act") are  incorporated by reference
herein:

     1. The Registrant's Annual Report on Form 10-K, as amended,  for the fiscal
year ended December 31, 1996.

     2.   The Registrant's Quarterly Reports on Form 10-Q for the periods ended
March 31, 1997 and June 30, 1997.

     3.   The Registrant's Current Report on Form 8-K, dated January 20, 1997.

     4. The  description of the  Registrant's  common stock,  par value $.01 per
share (the "Unilab Common Stock"),  contained in the  Registrant's  Registration
Statement on Form 8-A filed with the Commission on March 19, 1996, including any
amendments or reports filed for the purpose of updating such description.

     All  documents  filed with the  Commission  by the  Registrant  pursuant to
Sections  13(a),  13(c),  14 and 15(d) of the 1934 Act subsequent to the date of
this  Registration  Statement  and  prior  to  the  filing  of a  post-effective
amendment which  indicates that all securities  offered herein have been sold or
which  deregisters  all securities  then remaining  unsold shall be deemed to be
incorporated  by reference  into this  Registration  Statement  and to be a part
hereof from the date of filing of such documents.

     Any statement  contained herein or in a document  incorporated or deemed to
be incorporated by reference herein shall be deemed to be modified or superseded
for purposes hereof or of the related  prospectus to the extent that a statement
contained  herein  or in any other  subsequently  filed  document  which is also
incorporated  or deemed to be  incorporated  herein  modifies or supersedes such
statement.  Any such  statement so modified or  superseded  shall not be deemed,
except as so modified or superseded,  to constitute a part of this  Registration
Statement.

Item 4.   Description of Securities.

     Not Applicable, see Item 3(4) above.

Item 5.   Interests of Named Experts and Counsel.

     Mark  L.  Bibi,  Vice  President,  Secretary  and  General  Counsel  of the
Registrant,  is named in the Reoffer  Prospectus as having given an opinion upon
the validity of the securities being registered.  Mark L. Bibi has been the Vice
President,  Secretary and General Counsel of the Registrant for  approximately 4
years and beneficially owns 212,250 shares of the Registrant's Common Stock.

Item 6.   Indemnification of Directors and Officers.

     Section 145 of the General  Corporation  Law of the State of Delaware  (the
"DGCL")  provides that a Delaware  corporation  may indemnify any person against
expenses,  judgments,  fines  and  amounts  paid  in  settlements  actually  and
reasonably incurred by any such person in connection with a threatened,  pending
or completed action, suit or proceeding in which he is involved by reason of the
fact  that  he  is or  was a  director,  officer,  employee  or  agent  of  such
corporation,  or is or was  serving  at the  request  of the  corporation,  as a
director, officer, employee or agent of another corporation,  partnership, joint
venture, trust or other enterprise, provided that (i) he acted in good faith and
in a manner he reasonably believed to be in or not opposed to the best interests
of the  corporation  and (ii) with respect to any criminal action or proceeding,
he had no reasonable cause to believe his conduct was unlawful. If the action or
suit is by or in the name of the corporation,  the corporation may indemnify any
such  person  against  expenses  actually  and  reasonably  incurred  by  him in
connection  with the defense or settlement of such action or suit if he acted in
good faith and in a manner he reasonably believed to be in or not opposed to the
best interests of the corporation, except that no indemnification may be made in
respect of any claim,  issue or matter as to which such  person  shall have been
adjudged to be liable to the corporation, unless and only to the extent that the
Delaware  Court of  Chancery or the court in which the action or suit is brought
determines upon application  that,  despite the adjudication of liability but in
view of all the  circumstances of the case, such person is fairly and reasonably
entitled to indemnity for such expenses as the court deems proper.
<PAGE>
     The Amended and Restated  Certificate of  Incorporation,  as amended,  (the
"Certificate of Incorporation") of the Registrant provides for  indemnification,
to the fullest  extent  permitted by the  provisions of the DGCL, of all persons
whom it may indemnify pursuant thereto.  The Certificate of Incorporation of the
Registrant also provides that the indemnification provided by such section shall
not limit or exclude any rights,  indemnities  or  limitations  of  liability to
which any person may be entitled  whether as a matter of law,  under the Amended
and Restated By-laws of the Registrant,  by agreement,  vote of the stockholders
or disinterested directors of the Registrant or otherwise.

     In  accordance  with Section  102(b)(7)  of the DGCL,  the  Certificate  of
Incorporation of the Registrant  limits the personal  liability of the directors
of the Registrant to the fullest extent permitted by such Section 102(b)(7).

     The Registrant  also  maintains  standard forms of officers' and directors'
liability insurance policies.

Item 7.  Exemption from Registration Claimed.

     Exemption from registration for 2,979,261 shares of the Unilab Common Stock
covered  by the  Reoffer  Prospectus  was  claimed  under  Section  4(2)  of the
Securities  Act. Such shares were issued to certain  employees,  consultants and
directors  of  the   Registrant  as  part  of  their   individually   negotiated
compensation arrangements with the Registrant.

Item 8.   Exhibits.

     The  following  is a  complete  list of  exhibits  filed  as a part of this
registration statement:


Exhibit No.     Document

  4.01        Form of Unilab Corporation 1997 Directors Stock Purchase Plan.

  4.02        Form of Restricted Stock Agreement by and between the Registrant
              and Messrs. and Mesdames Brett, Bryan, Filer, Fischinger,
              Lanzolatta and Marquez.

  4.03        Form of Stock Option Agreement by and between the Registrant and
              Richard A. Michaelson.

  4.04        Restricted Stock Agreement, dated January 20, 1997, by
              and  between  the   Registrant  and  Andrew  H.  Baker
              (Incorporated  by  reference  to Exhibit  10.18 to the
              Company's  Form 10-K for the year ended  December  31,
              1996, dated March 21, 1997).

  4.05        Amendment No. 1 to Restricted Stock Agreement, dated January 20,
              1997, by and between the Registrant and Andrew H. Baker.

  4.06        Employment  Agreement,  dated January 20, 1997, by and
              between   the   Registrant   and   David   C.   Weavil
              (Incorporated  by  reference  to Exhibit  10.12 to the
              Company's  Annual  Report  on form  10-K  for the year
              ended December 31, 1996, dated March 21, 1997).

  5.01        Opinion of Mark L. Bibi, Vice President, Secretary and
              General  Counsel  for the  Registrant,  regarding  the
              legality of Common Stock being registered.

 23.01        Consent of Arthur Andersen LLP.

 23.02        Consent of Mark L. Bibi, Esq. (included in Exhibit 5.01 hereto).

 24.01        Powers of Attorney (included on the signature pages of this
              Registration Statement).

<PAGE>

Item No. 9.    Undertakings.

     (a)  The undersigned Registrant hereby undertakes:

          (1) to file,  during  any  period  in which  offers or sales are being
made, a post-effective amendment to this registration statement:

       (i)    To include any prospectus required by Section 10(a)(3) of the 1933
Act;

       (ii) To reflect in the  prospectus  any facts or events arising after the
   effective   date  of  the   registration   statement   (or  the  most  recent
   post-effective  amendment  thereof) which,  individually or in the aggregate,
   represent  a  fundamental   change  in  the  information  set  forth  in  the
   registration  statement.  Notwithstanding  the  foregoing,  any  increase  or
   decrease  in volume of  securities  offered  (if the  total  dollar  value of
   securities  offered  would not  exceed  that  which was  registered)  and any
   deviation  from the low or high and of the estimated  maximum  offering range
   may be reflected in the form of prospectus filed with the Commission pursuant
   to Rule  424(b)  if,  in the  aggregate,  the  changes  in  volume  and price
   represent no more than 20 percent  change in the maximum  aggregate  offering
   price  set  forth in the  "Calculation  of  Registration  Fee"  table in this
   registration statement; and

       (iii) To include any  material  information  with  respect to the plan of
   distribution not previously  disclosed in the  registration  statement or any
   material change to such information in the registration statement;

provided,  however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the
information to be included in a post-effective  amendment by those paragraphs is
contained in periodic  reports filed with or furnished to the  Commission by the
Registrant  pursuant  to Section  13 or  Section  15(d) of the 1934 Act that are
incorporated by reference in the registration statement.

       (2) that,  for the purpose of  determining  any liability  under the 1933
Act, each such post-effective amendment shall be deemed to be a new registration
statement relating to the securities  offered therein,  and the offering of such
securities  at that time shall be deemed to be the  initial  bona fide  offering
thereof; and

       (3) to remove from  registration by means of a  post-effective  amendment
any of the securities being registered which remain unsold at the termination of
the offering.

       (b) The undersigned  Registrant  hereby  undertakes that, for purposes of
determining  any liability  under the 1933 Act, each filing of the  Registrant's
Annual  Report  pursuant to Section 13(a) or Section 15(d) of the 1934 Act (and,
where  applicable,  each  filing of an employee  benefit  plan's  Annual  Report
pursuant to Section 15(d) of the 1934 Act) that is  incorporated by reference in
the registration  statement shall be deemed to be a new  registration  statement
relating to the securities offered therein,  and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

       (c) Insofar as indemnification for liabilities arising under the 1933 Act
may  be  permitted  to  directors,  officers  and  controlling  persons  of  the
Registrant pursuant to the foregoing  provisions,  or otherwise,  the Registrant
has been advised that in the opinion of the Securities  and Exchange  Commission
such  indemnification  is against  public policy as expressed in the Act and is,
therefore,  unenforceable. In the event that a claim for indemnification against
such liabilities  (other than the payment by the Registrant of expenses incurred
or paid by a director,  officer or  controlling  person of the Registrant in the
successful  defense of any  action,  suit or  proceeding)  is  asserted  by such
director,  officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been  settled by  controlling  precedent,  submit to a court of  appropriate
jurisdiction the question whether such  indemnification  by it is against public
policy as expressed in the Act and will be governed by the final adjudication of
such issue.

<PAGE>

REOFFER 
PROSPECTUS

                               UNILAB CORPORATION

                     COMMON STOCK, PAR VALUE $.01 PER SHARE

                                3,004,261 SHARES

     This Reoffer  Prospectus relates to the subsequent resale or offer for sale
on The American  Stock  Exchange,  or otherwise,  of (i) 25,000 shares of voting
common  stock,  par value  $.01 per share  ("Unilab  Common  Stock"),  of Unilab
Corporation,  a Delaware  corporation  ("Unilab" or the "Company"),  that may be
acquired by an employee of the Company, who could be deemed to be an "affiliate"
(as defined in Rule 405 promulgated under the Securities Act of 1933, as amended
(the  "Securities  Act"))  of  Unilab,  pursuant  to  the  exercise  of  certain
nonqualified  options granted to such employee under a Nonqualified Stock Option
Agreement (the "Option Shares") and (ii) 2,979,261  shares of restricted  Unilab
Common Stock (the "Restricted  Shares") that have been granted by the Company to
certain  employees,   consultants  and  directors  of  the  Company  as  partial
compensation for services rendered by such employees,  consultants and directors
(such  persons   referred  to  in  clauses  (i)  and  (ii)  being  the  "Selling
Stockholders"). In connection with such resales or offers for sale, such persons
and the  brokers  through  whom  such  shares  may be sold may be  deemed  to be
"underwriters"  as that term is defined in Section 2(11) of the Securities  Act.
The Company will not receive any proceeds from the offering of the Option Shares
or the Restricted  Shares.  All expenses of registration  incurred in connection
with  the  registration  under  the  Securities  Act  and  the  offering  of the
securities hereby are being borne by Unilab, but all selling and other expenses,
incurred by an  individual  Selling  Stockholder  will be borne by such  Selling
Stockholder.

     


THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE SECURITIES AND
   EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION NOR HAS THE
      SECURITIES AND EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION
         PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS.  ANY
            REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.


     No person is  authorized in connection  with any offering made hereby to
give any  information  or to make any
representation,  not contained in this Reoffer Prospectus, and if given or made,
such  information  or  representations  must not be relied  upon as having  been
authorized  by the Company or any Selling  Stockholder.  The Reoffer  Prospectus
does not  constitute an offer to sell or a  solicitation  of an offer to buy any
security other than the  securities  offered  hereby,  nor does it constitute an
offer to sell or a solicitation of an offer to buy any of the securities offered
hereby to any person in any  jurisdiction  in which it is  unlawful  to make any
such offer or solicitation to such person.  Neither the delivery of this Reoffer
Prospectus nor any sale made hereby shall under any circumstance  imply that the
information  contained  herein is correct as of any date  subsequent to the date
hereof.



   
              The date of this Reoffer Prospectus is August 8, 1997

<PAGE>


                              AVAILABLE INFORMATION

     The Company is subject to the informational  requirements of the Securities
Exchange  Act of 1934,  as  amended  (the  "Exchange  Act"),  and in  accordance
therewith is required to file reports,  proxy  statements and other  information
with the  Securities and Exchange  Commission  (the  "Commission")  which may be
inspected  and  copied at the  public  reference  facilities  maintained  by the
Commission  located at  Judiciary  Plaza,  450 Fifth  Street,  N.W.,  Room 1024,
Washington,  D.C. 20549, and at the public reference  facilities  located at the
regional offices of the Commission at Seven World Trade Center,  Suite 1300, New
York, New York 10048, and at the Citicorp Center, 500 West Madison Street, Suite
1400, Chicago,  Illinois 60661. Copies of such material can be obtained from the
Public Reference Section of the Commission at Judiciary Plaza, 450 Fifth Street,
N.W.,  Washington,  D.C. 20549, at prescribed rates. In addition, the Commission
maintains a Web site that contains reports, proxy and information statements and
other  information  regarding  registrants  that  file  electronically  with the
Commission.  The address of such site is  http://www.sec.gov.  The Company files
electronically with the Commission.  Unilab Common Stock is listed and traded on
The American Stock Exchange. Reports, proxy statements, informational statements
and other information  concerning the Company can be inspected at the offices of
The American Stock Exchange located at 86 Trinity Place, New York, NY 10006.

     The Company has filed with the Commission a registration  statement on Form
S-8 (herein,  together  with all  amendments,  exhibits and  schedules  thereto,
referred to as the  "Registration  Statement") under the Securities Act of 1933,
as amended  (the  "Securities  Act"),  with  respect to the  securities  offered
hereby.  This Reoffer  Prospectus,  which constitutes a part of the Registration
Statement, does not contain all of the information set forth in the Registration
Statement,  certain parts of which are omitted in accordance  with the rules and
regulations  of the  Commission,  and to which  reference  is hereby  made.  For
further information,  reference is hereby made to the Registration Statement and
exhibits  filed as a part thereof and otherwise  incorporated  therein and which
may be inspected  and copied in the manner and at the sources  described  above.
Statements  contained  in this  Reoffer  Prospectus  as to the  contents  of any
document  referred  to  are  not  necessarily  complete,  and in  each  instance
reference is made to such exhibit for a more complete  description and each such
statement is qualified in its entirety by such reference.

                                   THE COMPANY

General

     Unilab  primarily   provides  clinical   laboratory   testing  services  to
physicians,   managed-care  organizations,   hospitals  and  other  health  care
providers.  It provides clinical  laboratory  testing services through (i) three
full-service central testing laboratories located in Tarzana (Los Angeles),  San
Jose and Sacramento,  California,  (ii) approximately 40 STAT ("short turnaround
time")  laboratories in California and (iii)  approximately  217 patient service
centers primarily located in California, with a handful in certain other states.

     Unilab was incorporated  under the name MetCal Inc. on January 6, 1993 as a
Delaware corporation and successor to Unilab Corporation, a Colorado corporation
founded in 1988 (as  successor  to a  corporation  founded  in 1986),  which was
reincorporated in 1990 as a Delaware corporation. Unilab's executive offices are
located at 18448 Oxnard Street,  Tarzana,  California  91356,  telephone  number
(818)  996-7300.  Unilab Common Stock is listed on The American  Stock  Exchange
under the symbol "ULB."

                                 USE OF PROCEEDS

     The Company  will  receive  the  exercise  price of the Option  Shares when
exercised by the holder thereof.  Such proceeds will be used for working capital
purposes.  The Company  will not receive any  proceeds  from the offering of the
Restricted Shares by the Selling Stockholders.



<PAGE>



                               PLAN OF DISTRIBUTION

     The shares of Unilab  Common Stock covered by this Reoffer  Prospectus  are
being registered by Unilab for account of the Selling  Stockholders.  Unilab has
been  informed  by the  Selling  Stockholders  that none of such  shares will be
offered through underwriters.

     The  shares of Unilab  Common  Stock  reoffered  and  resold  hereby may be
offered  and sold from time to time by certain  stockholders  of Unilab  through
brokers on The American Stock Exchange or otherwise  (without the payment of any
underwriting  commission or discount other than normal brokers'  commissions for
effecting such transactions),  through negotiated  transactions or otherwise, at
market  prices  prevailing  at the  time of  sale,  at  prices  related  to such
prevailing  market prices or at prices  otherwise  negotiated.  To the Company's
knowledge  no specific  brokers or dealers have been  designated  by the Selling
Stockholders  nor has any  agreement  been  entered into in respect of brokerage
commissions or for the exclusive or coordinated sale of any securities which may
be reoffered pursuant to this Reoffer Prospectus.  The Selling  Stockholders and
any broker or dealer  through  whom  offers or sales of shares of Unilab  Common
Stock  covered  by  this  Reoffer   Prospectus  are  made  may  be  regarded  as
"underwriters"  within the meaning of the Act, although the Selling Stockholders
disclaim  such  status.  Compensation  received  by any such broker or dealer in
respect of the offer or sale of such  shares may be  regarded  as  underwriters'
compensation.

     All expenses of registration  incurred in connection with this offering are
being  borne by  Unilab,  but all  selling  and other  expenses  incurred  by an
individual Selling Stockholder will be borne by such Selling Stockholder.

                              SELLING STOCKHOLDERS

     This Reoffer  Prospectus relates to (i) shares of Unilab Common Stock which
have been  acquired  by certain  employees,  consultants  and  directors  of the
Company  pursuant  to the grant to such  persons of Unilab  Common  Stock  under
Restricted Stock Agreements and/or employment agreements,  (ii) shares of Unilab
Common  Stock  which may be  acquired by an employee of the Company who could be
deemed to be an  "affiliate"  of Unilab,  pursuant  to the  exercise  of options
granted to such employee under a Nonqualified  Stock Option  Agreement and (iii)
shares of Unilab Common Stock which have been acquired by a certain  director of
the Company pursuant to the 1997 Unilab Director Stock Purchase Plan.

     The  following  table  sets  forth  certain  information  known  to  Unilab
regarding the  beneficial  ownership of Unilab Common Stock as of August 1, 1997
with respect to each of the Selling Stockholders.  For purposes of this table, a
person is deemed to have "beneficial ownership" of any shares as of a given date
which such person has the right to acquire  within 60 days after such date.  For
purposes of computing the percentage of  outstanding  shares held by each person
named below on a given  date,  any  security  which such person has the right to
acquire within 60 days after such date is deemed to be  outstanding,  but is not
deemed to be outstanding  for the purpose of computing the percentage  ownership
of any other  person.  Except as noted  below,  each  person has full voting and
investment power over the shares indicated.



<PAGE>
<TABLE>
<CAPTION>
                                                  Number of shares of
                         Position or Material     Common Stock                              Number of Shares of
Selling                  Relationship with        Beneficially Owned     Number of Shares   Common Stock Beneficially
Stockholder              the Company During            Prior to          of Common Stock    Owned After Completion
                         Past Three Years         Reoffering (1)          Reoffered         of the Reoffering(1)
                                                  
                                                                                                      Percentage of 
                                                                                            Number    Total Shares
                                                                                                      Outstanding
<S>                       <C>                      <C>                     <C>            <C>            <C>
David C. Weavil           Chairman, Chief          1,371,428               1,371,428             0          *
                          Executive Officer and
                          President

Kirby L. Cramer           Director                 1,011,611                 500,000       511,611        1.3%


Todd Brett                Associate Vice               4,833                   1,500         3,333          *
                          President, Business
                          Development

Lauren Bryan              Former Divisional Vice      18,500                   1,500        17,000          *
                          President

David Filer               Vice President of           16,666                  10,000         6,666          *
                          Billing

Andrew Fischinger         Regional Medical            10,000                  10,000             0          *
                          Director

Jeff Lanzolatta           Division President         175,000                  50,000       125,000          *
 
Beverly Marquez           Regional General             4,833                   1,500         3,333          *
                          Manager

Richard A. Michaelson     Senior Vice President,     535,340                  25,000       510,340        1.3
                          Chief Financial
                          Officer and Treasurer

Andrew H. Baker           Consultant; Former       2,716,288               1,033,333     1,682,955        4.2
                          Chairman, Chief
                          Executive Officer and
                          President
</TABLE>

------------------------
*  Less than 1%.

(1)  Calculated  pursuant to Rule 13d-3  promulgated under the Exchange Act, and
     based on 40,263,977  shares of Unilab Common Stock outstanding as of August
     1, 1997.  Since the shares  being  reoffered  hereby  have been  registered
     pursuant  to Rule 415  under  the  Securities  Act and not  pursuant  to an
     underwritten  public offering,  the number of registered  shares to be sold
     pursuant hereto and the dates of such sale are not presently determinable.

     On August 4, 1997 the closing  sales  price per share of the Unilab  Common
     Stock, as reported on the American Stock Exchange was $1.375.

<PAGE>
                       DOCUMENTS INCORPORATED BY REFERENCE


     The  following   documents   previously  filed  with  the  Commission  (the
"Commission")  by the Company pursuant to the Securities Act or the Exchange Act
are incorporated by reference herein and made a part hereof:

     1. The Company's  Annual  Report on Form 10-K,  as amended,  for the fiscal
year ended December 31, 1996.

     2.   The Company's Quarterly Reports on Form 10-Q for the periods ended
March 31, 1997 and June 30, 1997.

     3.   The Registrant's Current Report on Form 8-K, dated January 20, 1997

     4. The description of the Company's  Common Stock, par value $.01 per share
(the "Unilab Common Stock"),  contained in the Company's  Registration Statement
on Form 8-A filed with the Commission on June 19, 1996, including any amendments
or reports filed for the purpose of updating such description.

     All documents filed with the Commission by the Company pursuant to Sections
13(a),  13(c),  14 and  15(d)  of the 1934  Act  subsequent  to the date of this
Registration  Statement  and prior to the filing of a  post-effective  amendment
which  indicates  that all  securities  offered  herein  have been sold or which
deregisters  all  securities  then  remaining  unsold  shall  be  deemed  to  be
incorporated  by reference into this Reoffer  Prospectus and to be a part hereof
from the date of filing of such documents.

     Any statement  contained herein or in a document  incorporated or deemed to
be incorporated by reference herein shall be deemed to be modified or superseded
for purposes  hereof to the extent that a statement  contained  herein or in any
other  subsequently  filed document which is also  incorporated  or deemed to be
incorporated herein modifies or supersedes such statement. Any such statement so
modified or superseded shall not be deemed, except as so modified or superseded,
to constitute a part of this Reoffer Prospectus.

     A copy of any  documents  incorporated  by  reference  in the  Registration
Statement (not including  exhibits to the  information  that is  incorporated by
reference unless such exhibits are  specifically  incorporated by reference into
the information  that the  Registration  Statement  incorporates)  of which this
Reoffer  Prospectus  forms a part but which is not  delivered  with this Reoffer
Prospectus  will be provided by the Company without charge to any person to whom
this Reoffer Prospectus has been delivered,  upon the oral or written request of
such person.  Such requests  should be directed to Mark L. Bibi, Vice President,
Secretary and General Counsel,  Unilab  Corporation,  401 Hackensack Avenue, 9th
Floor, Hackensack, New Jersey 07601, telephone number (201) 525-1000.

                         ACCOUNTING AND AUDITING EXPERTS

     The audited Financial Statements and schedules of the Company, incorporated
by reference  in this  Reoffer  Prospectus  and  elsewhere in this  Registration
Statement  have  been  audited  by  Arthur  Andersen  LLP,   independent  public
accountants,  as  indicated  in their  reports  with  respect  thereto,  and are
incorporated by reference  herein in reliance upon the authority of said firm as
experts in accounting and auditing in giving said reports.

                                  LEGAL MATTERS

     Certain legal matters with respect to the Common Stock being offered hereby
are being passed upon by Mark L. Bibi,  Vice  President,  Secretary  and General
Counsel to the Company.

<PAGE>
                                 INDEMNIFICATION

     Section 145 of the General  Corporation  Law of the State of Delaware  (the
"DGCL")  provides that a Delaware  corporation  may indemnify any person against
expenses,  judgments,  fines  and  amounts  paid  in  settlements  actually  and
reasonably incurred by any such person in connection with a threatened,  pending
or completed action, suit or proceeding in which he is involved by reason of the
fact  that  he  is or  was a  director,  officer,  employee  or  agent  of  such
corporation,  or is or was  serving  at the  request  of the  corporation,  as a
director, officer, employee or agent of another corporation,  partnership, joint
venture, trust or other enterprise, provided that (i) he acted in good faith and
in a manner he reasonably believed to be in or not opposed to the best interests
of the  corporation  and (ii) with respect to any criminal action or proceeding,
he had no reasonable cause to believe his conduct was unlawful. If the action or
suit is by or in the name of the corporation,  the corporation may indemnify any
such  person  against  expenses  actually  and  reasonably  incurred  by  him in
connection  with the defense or settlement of such action of suit if he acted in
good faith and in a manner he reasonably believed to be in or not opposed to the
best interests of the corporation, except that no indemnification may be made in
respect of any claim,  issue or matter as to which such  person  shall have been
adjudged to be liable to the corporation, unless and only to the extent that the
Delaware  Court of  Chancery or the court in which the action or suit is brought
determines upon application  that,  despite the adjudication of liability but in
the light of the circumstances of the case, such person is fairly and reasonably
entitled to indemnity for such expenses as the court deems proper.

     The Amended and Restated  Certificate of  Incorporation,  as amended,  (the
"Certificate of Incorporation") of the Company provides for indemnification,  to
the fullest extent  permitted by the provisions of the DGCL, of all persons whom
it may  indemnify  pursuant  thereto.  The  Certificate  of  Incorporation  also
provides  that the  indemnification  provided by such section shall not limit or
exclude any rights,  indemnities or limitations of liability to which any person
may be  entitled  whether as a matter of law,  under the  Amended  and  Restated
By-laws of the Company, by agreement,  vote of the stockholders or disinterested
directors of the Company or otherwise.

     In  accordance  with Section  102(b)(7)  of the DGCL,  the  Certificate  of
Incorporation  limits the personal  liability of the directors of the Company to
the fullest extent permitted by such Section 102(b)(7).

     The Company  also  maintains  standard  forms of officers'  and  directors'
liability insurance policies.



Unilab Corporation has filed with the Securities            3,004,261 Shares
and Exchange Commission, Washington, D.C., a
Registration Statement under the Securities Act of
1933, as amended, with respect to this offering.           UNILAB CORPORATION
This Reoffer Prospectus omits certain  information
contained in the Registration  Statement. The
information omitted may be obtained from the Securities
and  Exchange Commission upon payment of the regular        Common Stock,
charge therefor.                                        Par Value $.01 Per Share



                   TABLE OF CONTENTS

                                                 Page

Available Information.............................A-2         PROSPECTUS
The Company.......................................A-2
Use of Proceeds...................................A-2
Plan of Distribution..............................A-3
Selling Stockholders..............................A-3
Documents Incorporated by Reference...............A-5
Accounting and Auditing Experts...................A-5
Legal Matters.....................................A-5
Indemnification...................................A-6










                                                           August 8, 1997


<PAGE>

                                   SIGNATURES

The Registrant

     Pursuant to the  requirements of the Securities Act of 1933, the Registrant
certifies  that it has  reasonable  grounds to believe  that it meets all of the
requirements  for  filing  on Form S-8 and has  duly  caused  this  Registration
Statement  to be  signed  on  its  behalf  by  the  undersigned,  hereunto  duly
authorized,  in the City of Los Angeles and State of  California on this 8th day
of August, 1997.


                                     UNILAB CORPORATION



                                     By: /s/   David C. Weavil
                                     Name:    David C. Weavil
                                     Title:   Chairman of the Board, President
                                     and Chief Executive Officer
<PAGE>
                                POWER OF ATTORNEY

     KNOW ALL MEN BY THESE PRESENTS,  that each person whose  signature  appears
below hereby appoints Mark L. Bibi as his true and lawful attorney-in-fact, with
full power of substitution  and  resubstitution,  for him and in his name, place
and stead, in any and all capacities,  to sign any and all amendments (including
post-effective  amendments) to this Registration  Statement and to file the same
with all exhibits  thereto and other documents in connection  therewith with the
Securities  and Exchange  Commission  granting  unto said  attorney-in-fact  and
agents,  and each of them,  full power and  authority to do and perform each and
every act and thing requisite and necessary to be done in and about the premises
as fully to all intents and  purposes as he might or could do in person,  hereby
ratifying and confirming all that said attorney-in-fact and agents, or any them,
or his substitute, may lawfully do or cause to be done by virtue hereof.

     Pursuant  to  the   requirements  of  the  Securities  Act  of  1933,  this
Registration  Statement  has been signed below by the  following  persons in the
capacities and on the dated indicated.


Signature                     Title                              Date

      /s/
------------------------
David C. Weavil               Chairman of the Board,             August 8, 1997
                              President and Chief Executive
                              Officer (principal executive
                              officer)

      /s/
------------------------
Richard A. Michaelson         Senior Vice President-Finance,
                              Treasurer and Chief Financial
                              Officer (principal financial
                              and accounting)                    August 8, 1997

      /s/
------------------------
Kirby L. Cramer               Director                           August 8, 1997

      /s/
------------------------
Michael B. Hoffman            Director                           August 8, 1997

      /s/
------------------------
Haywood D. Cochrane           Director                           August 8, 1997

      /s/
------------------------
Gabriel B. Thomas             Director                           August 8, 1997



                                 EXHIBITS INDEX


Exhibit No.     Document

  4.01        Form of Unilab Corporation 1997 Directors Stock Purchase Plan.

  4.02        Form of Restricted Stock Agreement by and between the Registrant
              and Messrs. and Mesdames Brett, Bryan, Filer, Fischinger,
              Lanzolatta and Marquez.

  4.03        Form of Stock Option Agreement by and between the Registrant and
              Richard A. Michaelson.

  4.04        Restricted Stock Agreement, dated January 20, 1997, by
              and  between  the   Registrant  and  Andrew  H.  Baker
              (Incorporated  by  reference  to Exhibit  10.18 to the
              Company's  Form 10-K for the year ended  December  31,
              1996, dated March 21, 1997).

  4.05        Amendment No. 1 to Restricted Stock Agreement, dated January 20,
              1997, by and between the Registrant and Andrew H. Baker.

  4.06        Employment  Agreement,  dated January 20, 1997, by and
              between   the   Registrant   and   David   C.   Weavil
              (Incorporated  by  reference  to Exhibit  10.12 to the
              Company's  Annual  Report  on form  10-K  for the year
              ended December 31, 1996, dated March 21, 1997).

  5.01        Opinion of Mark L. Bibi, Vice President, Secretary and
              General  Counsel  for the  Registrant,  regarding  the
              legality of Common Stock being registered.

 23.01        Consent of Arthur Andersen LLP.

 23.02        Consent of Mark L. Bibi, Esq. (included in Exhibit 5.01 hereto).

 24.01        Powers of Attorney (included on the signature pages of this
              Registration Statement).
[{"type": "S-8", "sequence": "1", "secsgml_size_bytes": 44233}]
{"company-data": {"conformed-name": "UNILAB CORP /DE/", "cik": "0000899714", "assigned-sic": "8071", "irs-number": "954415490", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-33195", "film-number": "97654271"}, "business-address": {"street1": "18448 OXNARD ST", "city": "TARZANA", "state": "CA", "zip": "91356", "phone": "8189667300"}, "mail-address": {"street1": "UNILAB CORP", "street2": "401 HACKENSACK AVE 9TH FL", "city": "HACKENSACK", "state": "NJ", "zip": "07601"}, "former-company": {"former-conformed-name": "METCAL INC", "date-changed": "19930401"}}
As filed with the Securities and Exchange Commission on August 8, 1997

                                                     Registration No. 333-

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                               UNILAB CORPORATION
             (Exact name of Registrant as specified in its charter)

               Delaware                                95-4415490

       (State or jurisdiction of                    (I.R.S. Employer
    incorporation or organization)                    Identification No.)

                              18448 Oxnard Street
                            Tarzana, California 91356
                                 (818) 996-7300

              (Address,  including zip code, and telephone  number,
   including area code, of Registrant's  principal executive offices)

              UNILAB CORPORATION 1997 DIRECTORS STOCK PURCHASE PLAN
                 UNILAB CORPORATION NON-QUALIFIED STOCK OPTIONS
                   UNILAB CORPORATION RESTRICTED COMMON STOCK

                           (Full Title of the Plans)

                               Mark L. Bibi, Esq.
                          Vice President, Secretary and
                                 General Counsel
                               Unilab Corporation
                              401 Hackensack Avenue
                                    9th Floor
                          Hackensack, New Jersey 07601
                                 (201) 525-1000
                     (Name, address, including zip code, and
          telephone number, including area code, of agent for service)

                         CALCULATION OF REGISTRATION FEE
Title of Securities            Amount to be    Proposed Maximum    Proposed Maximum         Amount of
           to be Registered              Registered      Offering Price    Aggregate Offering     Registration Fee
                                                          Per Share(1)          Price(1)
Common Stock, par value $.01 per        4,004,261(2)         $1.375       $5,505,859             $1668
   share
(1)  Estimated  solely  for the  purpose of  calculating  the  registration  fee
     pursuant to Rule 457(c) and rule 457(h)  promulgated  under the  Securities
     Act of 1933, as amended (the "Securities  Act"),  based upon the average of
     the high and low prices per share of the Common Stock (such  average  being
     $1.375) as reported on The American Stock Exchange on August 4, 1997.

(2)  Represents  (i)  25,000  shares  issuable  upon  the  exercise  of  certain
     nonqualified  options  granted to an  employee;  (ii)  2,979,261  shares of
     restricted  stock issued to certain  employees,  consultants and directors;
     and  (iii)  1,000,000   shares  issuable  in  connection  with  The  Unilab
     Corporation 1997 Directors Stock Purchase Plan. This Registration Statement
     also relates to such indeterminate number of additional  shares of Common
     Stock as may be issuable as a result of stock splits, stock dividends or
     similar transactions.
UNILAB CORPORATION
 
                 FORM S-8 CROSS REFERENCE SHEET SHOWING LOCATION
                  OF INFORMATION REQUIRED BY PART I OF FORM S-3

     Form S-3 Item Number                        Location/Heading in Prospectus

1.   Forepart of Registration Statement and      Cover Page
     Outside Front Cover Page of Prospectus

2.   Inside Front and Outside Back Cover         Available Information;
     Pages of Prospectus                         Incorporation of Certain
                                                 Information by Reference

3.   Summary Information, Risk Factors           Not Applicable
     and Ratio of Earnings to Fixed Charges

4.   Use of Proceeds                             Use of Proceeds

5.   Determination of Offering Price             Not Applicable

6.   Dilution                                    Not Applicable

7.   Selling Security Holders                    Selling Stockholders

8.   Plan of Distribution                        Plan of Distribution

9.   Description of Securities                   Not Applicable
     to be Registered

10.  Interests of Named Experts and Counsel      Experts; Legal Matters

11.  Material Changes                            Not Applicable

12.  Incorporation of Certain Information        Incorporation of Certain
     by Reference                                Information by Reference

13.  Disclosure of Commission Position on        Indemnification of Officers
     Indemnification for Securities Act          and Directors
     Liabilities
PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.   Incorporation of Documents by Reference.

     The following  documents  previously filed with the Securities and Exchange
Commission (the "Commission") by Unilab Corporation (the "Registrant")  pursuant
to the  Securities  Act of 1933,  as amended (the "1933 Act") or the  Securities
Exchange Act of 1934, as amended (the "1934 Act") are  incorporated by reference
herein:

     1. The Registrant's Annual Report on Form 10-K, as amended,  for the fiscal
year ended December 31, 1996.

     2.   The Registrant's Quarterly Reports on Form 10-Q for the periods ended
March 31, 1997 and June 30, 1997.

     3.   The Registrant's Current Report on Form 8-K, dated January 20, 1997.

     4. The  description of the  Registrant's  common stock,  par value $.01 per
share (the "Unilab Common Stock"),  contained in the  Registrant's  Registration
Statement on Form 8-A filed with the Commission on March 19, 1996, including any
amendments or reports filed for the purpose of updating such description.

     All  documents  filed with the  Commission  by the  Registrant  pursuant to
Sections  13(a),  13(c),  14 and 15(d) of the 1934 Act subsequent to the date of
this  Registration  Statement  and  prior  to  the  filing  of a  post-effective
amendment which  indicates that all securities  offered herein have been sold or
which  deregisters  all securities  then remaining  unsold shall be deemed to be
incorporated  by reference  into this  Registration  Statement  and to be a part
hereof from the date of filing of such documents.

     Any statement  contained herein or in a document  incorporated or deemed to
be incorporated by reference herein shall be deemed to be modified or superseded
for purposes hereof or of the related  prospectus to the extent that a statement
contained  herein  or in any other  subsequently  filed  document  which is also
incorporated  or deemed to be  incorporated  herein  modifies or supersedes such
statement.  Any such  statement so modified or  superseded  shall not be deemed,
except as so modified or superseded,  to constitute a part of this  Registration
Statement.

Item 4.   Description of Securities.

     Not Applicable, see Item 3(4) above.

Item 5.   Interests of Named Experts and Counsel.

     Mark  L.  Bibi,  Vice  President,  Secretary  and  General  Counsel  of the
Registrant,  is named in the Reoffer  Prospectus as having given an opinion upon
the validity of the securities being registered.  Mark L. Bibi has been the Vice
President,  Secretary and General Counsel of the Registrant for  approximately 4
years and beneficially owns 212,250 shares of the Registrant's Common Stock.

Item 6.   Indemnification of Directors and Officers.

     Section 145 of the General  Corporation  Law of the State of Delaware  (the
"DGCL")  provides that a Delaware  corporation  may indemnify any person against
expenses,  judgments,  fines  and  amounts  paid  in  settlements  actually  and
reasonably incurred by any such person in connection with a threatened,  pending
or completed action, suit or proceeding in which he is involved by reason of the
fact  that  he  is or  was a  director,  officer,  employee  or  agent  of  such
corporation,  or is or was  serving  at the  request  of the  corporation,  as a
director, officer, employee or agent of another corporation,  partnership, joint
venture, trust or other enterprise, provided that (i) he acted in good faith and
in a manner he reasonably believed to be in or not opposed to the best interests
of the  corporation  and (ii) with respect to any criminal action or proceeding,
he had no reasonable cause to believe his conduct was unlawful. If the action or
suit is by or in the name of the corporation,  the corporation may indemnify any
such  person  against  expenses  actually  and  reasonably  incurred  by  him in
connection  with the defense or settlement of such action or suit if he acted in
good faith and in a manner he reasonably believed to be in or not opposed to the
best interests of the corporation, except that no indemnification may be made in
respect of any claim,  issue or matter as to which such  person  shall have been
adjudged to be liable to the corporation, unless and only to the extent that the
Delaware  Court of  Chancery or the court in which the action or suit is brought
determines upon application  that,  despite the adjudication of liability but in
view of all the  circumstances of the case, such person is fairly and reasonably
entitled to indemnity for such expenses as the court deems proper.
The Amended and Restated  Certificate of  Incorporation,  as amended,  (the
"Certificate of Incorporation") of the Registrant provides for  indemnification,
to the fullest  extent  permitted by the  provisions of the DGCL, of all persons
whom it may indemnify pursuant thereto.  The Certificate of Incorporation of the
Registrant also provides that the indemnification provided by such section shall
not limit or exclude any rights,  indemnities  or  limitations  of  liability to
which any person may be entitled  whether as a matter of law,  under the Amended
and Restated By-laws of the Registrant,  by agreement,  vote of the stockholders
or disinterested directors of the Registrant or otherwise.

     In  accordance  with Section  102(b)(7)  of the DGCL,  the  Certificate  of
Incorporation of the Registrant  limits the personal  liability of the directors
of the Registrant to the fullest extent permitted by such Section 102(b)(7).

     The Registrant  also  maintains  standard forms of officers' and directors'
liability insurance policies.

Item 7.  Exemption from Registration Claimed.

     Exemption from registration for 2,979,261 shares of the Unilab Common Stock
covered  by the  Reoffer  Prospectus  was  claimed  under  Section  4(2)  of the
Securities  Act. Such shares were issued to certain  employees,  consultants and
directors  of  the   Registrant  as  part  of  their   individually   negotiated
compensation arrangements with the Registrant.

Item 8.   Exhibits.

     The  following  is a  complete  list of  exhibits  filed  as a part of this
registration statement:

Exhibit No.     Document

  4.01        Form of Unilab Corporation 1997 Directors Stock Purchase Plan.

  4.02        Form of Restricted Stock Agreement by and between the Registrant
              and Messrs. and Mesdames Brett, Bryan, Filer, Fischinger,
              Lanzolatta and Marquez.

  4.03        Form of Stock Option Agreement by and between the Registrant and
              Richard A. Michaelson.

  4.04        Restricted Stock Agreement, dated January 20, 1997, by
              and  between  the   Registrant  and  Andrew  H.  Baker
              (Incorporated  by  reference  to Exhibit  10.18 to the
              Company's  Form 10-K for the year ended  December  31,
              1996, dated March 21, 1997).

  4.05        Amendment No. 1 to Restricted Stock Agreement, dated January 20,
              1997, by and between the Registrant and Andrew H. Baker.

  4.06        Employment  Agreement,  dated January 20, 1997, by and
              between   the   Registrant   and   David   C.   Weavil
              (Incorporated  by  reference  to Exhibit  10.12 to the
              Company's  Annual  Report  on form  10-K  for the year
              ended December 31, 1996, dated March 21, 1997).

  5.01        Opinion of Mark L. Bibi, Vice President, Secretary and
              General  Counsel  for the  Registrant,  regarding  the
              legality of Common Stock being registered.

 23.01        Consent of Arthur Andersen LLP.

 23.02        Consent of Mark L. Bibi, Esq. (included in Exhibit 5.01 hereto).

 24.01        Powers of Attorney (included on the signature pages of this
              Registration Statement).
Item No. 9.    Undertakings.

     (a)  The undersigned Registrant hereby undertakes:

          (1) to file,  during  any  period  in which  offers or sales are being
made, a post-effective amendment to this registration statement:

       (i)    To include any prospectus required by Section 10(a)(3) of the 1933
Act;

       (ii) To reflect in the  prospectus  any facts or events arising after the
   effective   date  of  the   registration   statement   (or  the  most  recent
   post-effective  amendment  thereof) which,  individually or in the aggregate,
   represent  a  fundamental   change  in  the  information  set  forth  in  the
   registration  statement.  Notwithstanding  the  foregoing,  any  increase  or
   decrease  in volume of  securities  offered  (if the  total  dollar  value of
   securities  offered  would not  exceed  that  which was  registered)  and any
   deviation  from the low or high and of the estimated  maximum  offering range
   may be reflected in the form of prospectus filed with the Commission pursuant
   to Rule  424(b)  if,  in the  aggregate,  the  changes  in  volume  and price
   represent no more than 20 percent  change in the maximum  aggregate  offering
   price  set  forth in the  "Calculation  of  Registration  Fee"  table in this
   registration statement; and

       (iii) To include any  material  information  with  respect to the plan of
   distribution not previously  disclosed in the  registration  statement or any
   material change to such information in the registration statement;

provided,  however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the
information to be included in a post-effective  amendment by those paragraphs is
contained in periodic  reports filed with or furnished to the  Commission by the
Registrant  pursuant  to Section  13 or  Section  15(d) of the 1934 Act that are
incorporated by reference in the registration statement.

       (2) that,  for the purpose of  determining  any liability  under the 1933
Act, each such post-effective amendment shall be deemed to be a new registration
statement relating to the securities  offered therein,  and the offering of such
securities  at that time shall be deemed to be the  initial  bona fide  offering
thereof; and

       (3) to remove from  registration by means of a  post-effective  amendment
any of the securities being registered which remain unsold at the termination of
the offering.

       (b) The undersigned  Registrant  hereby  undertakes that, for purposes of
determining  any liability  under the 1933 Act, each filing of the  Registrant's
Annual  Report  pursuant to Section 13(a) or Section 15(d) of the 1934 Act (and,
where  applicable,  each  filing of an employee  benefit  plan's  Annual  Report
pursuant to Section 15(d) of the 1934 Act) that is  incorporated by reference in
the registration  statement shall be deemed to be a new  registration  statement
relating to the securities offered therein,  and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

       (c) Insofar as indemnification for liabilities arising under the 1933 Act
may  be  permitted  to  directors,  officers  and  controlling  persons  of  the
Registrant pursuant to the foregoing  provisions,  or otherwise,  the Registrant
has been advised that in the opinion of the Securities  and Exchange  Commission
such  indemnification  is against  public policy as expressed in the Act and is,
therefore,  unenforceable. In the event that a claim for indemnification against
such liabilities  (other than the payment by the Registrant of expenses incurred
or paid by a director,  officer or  controlling  person of the Registrant in the
successful  defense of any  action,  suit or  proceeding)  is  asserted  by such
director,  officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been  settled by  controlling  precedent,  submit to a court of  appropriate
jurisdiction the question whether such  indemnification  by it is against public
policy as expressed in the Act and will be governed by the final adjudication of
such issue.
REOFFER 
PROSPECTUS

                               UNILAB CORPORATION

                     COMMON STOCK, PAR VALUE $.01 PER SHARE

                                3,004,261 SHARES

     This Reoffer  Prospectus relates to the subsequent resale or offer for sale
on The American  Stock  Exchange,  or otherwise,  of (i) 25,000 shares of voting
common  stock,  par value  $.01 per share  ("Unilab  Common  Stock"),  of Unilab
Corporation,  a Delaware  corporation  ("Unilab" or the "Company"),  that may be
acquired by an employee of the Company, who could be deemed to be an "affiliate"
(as defined in Rule 405 promulgated under the Securities Act of 1933, as amended
(the  "Securities  Act"))  of  Unilab,  pursuant  to  the  exercise  of  certain
nonqualified  options granted to such employee under a Nonqualified Stock Option
Agreement (the "Option Shares") and (ii) 2,979,261  shares of restricted  Unilab
Common Stock (the "Restricted  Shares") that have been granted by the Company to
certain  employees,   consultants  and  directors  of  the  Company  as  partial
compensation for services rendered by such employees,  consultants and directors
(such  persons   referred  to  in  clauses  (i)  and  (ii)  being  the  "Selling
Stockholders"). In connection with such resales or offers for sale, such persons
and the  brokers  through  whom  such  shares  may be sold may be  deemed  to be
"underwriters"  as that term is defined in Section 2(11) of the Securities  Act.
The Company will not receive any proceeds from the offering of the Option Shares
or the Restricted  Shares.  All expenses of registration  incurred in connection
with  the  registration  under  the  Securities  Act  and  the  offering  of the
securities hereby are being borne by Unilab, but all selling and other expenses,
incurred by an  individual  Selling  Stockholder  will be borne by such  Selling
Stockholder.

     

THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE SECURITIES AND
   EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION NOR HAS THE
      SECURITIES AND EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION
         PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS.  ANY
            REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

     No person is  authorized in connection  with any offering made hereby to
give any  information  or to make any
representation,  not contained in this Reoffer Prospectus, and if given or made,
such  information  or  representations  must not be relied  upon as having  been
authorized  by the Company or any Selling  Stockholder.  The Reoffer  Prospectus
does not  constitute an offer to sell or a  solicitation  of an offer to buy any
security other than the  securities  offered  hereby,  nor does it constitute an
offer to sell or a solicitation of an offer to buy any of the securities offered
hereby to any person in any  jurisdiction  in which it is  unlawful  to make any
such offer or solicitation to such person.  Neither the delivery of this Reoffer
Prospectus nor any sale made hereby shall under any circumstance  imply that the
information  contained  herein is correct as of any date  subsequent to the date
hereof.

   
              The date of this Reoffer Prospectus is August 8, 1997
AVAILABLE INFORMATION

     The Company is subject to the informational  requirements of the Securities
Exchange  Act of 1934,  as  amended  (the  "Exchange  Act"),  and in  accordance
therewith is required to file reports,  proxy  statements and other  information
with the  Securities and Exchange  Commission  (the  "Commission")  which may be
inspected  and  copied at the  public  reference  facilities  maintained  by the
Commission  located at  Judiciary  Plaza,  450 Fifth  Street,  N.W.,  Room 1024,
Washington,  D.C. 20549, and at the public reference  facilities  located at the
regional offices of the Commission at Seven World Trade Center,  Suite 1300, New
York, New York 10048, and at the Citicorp Center, 500 West Madison Street, Suite
1400, Chicago,  Illinois 60661. Copies of such material can be obtained from the
Public Reference Section of the Commission at Judiciary Plaza, 450 Fifth Street,
N.W.,  Washington,  D.C. 20549, at prescribed rates. In addition, the Commission
maintains a Web site that contains reports, proxy and information statements and
other  information  regarding  registrants  that  file  electronically  with the
Commission.  The address of such site is  http://www.sec.gov.  The Company files
electronically with the Commission.  Unilab Common Stock is listed and traded on
The American Stock Exchange. Reports, proxy statements, informational statements
and other information  concerning the Company can be inspected at the offices of
The American Stock Exchange located at 86 Trinity Place, New York, NY 10006.

     The Company has filed with the Commission a registration  statement on Form
S-8 (herein,  together  with all  amendments,  exhibits and  schedules  thereto,
referred to as the  "Registration  Statement") under the Securities Act of 1933,
as amended  (the  "Securities  Act"),  with  respect to the  securities  offered
hereby.  This Reoffer  Prospectus,  which constitutes a part of the Registration
Statement, does not contain all of the information set forth in the Registration
Statement,  certain parts of which are omitted in accordance  with the rules and
regulations  of the  Commission,  and to which  reference  is hereby  made.  For
further information,  reference is hereby made to the Registration Statement and
exhibits  filed as a part thereof and otherwise  incorporated  therein and which
may be inspected  and copied in the manner and at the sources  described  above.
Statements  contained  in this  Reoffer  Prospectus  as to the  contents  of any
document  referred  to  are  not  necessarily  complete,  and in  each  instance
reference is made to such exhibit for a more complete  description and each such
statement is qualified in its entirety by such reference.

                                   THE COMPANY

General

     Unilab  primarily   provides  clinical   laboratory   testing  services  to
physicians,   managed-care  organizations,   hospitals  and  other  health  care
providers.  It provides clinical  laboratory  testing services through (i) three
full-service central testing laboratories located in Tarzana (Los Angeles),  San
Jose and Sacramento,  California,  (ii) approximately 40 STAT ("short turnaround
time")  laboratories in California and (iii)  approximately  217 patient service
centers primarily located in California, with a handful in certain other states.

     Unilab was incorporated  under the name MetCal Inc. on January 6, 1993 as a
Delaware corporation and successor to Unilab Corporation, a Colorado corporation
founded in 1988 (as  successor  to a  corporation  founded  in 1986),  which was
reincorporated in 1990 as a Delaware corporation. Unilab's executive offices are
located at 18448 Oxnard Street,  Tarzana,  California  91356,  telephone  number
(818)  996-7300.  Unilab Common Stock is listed on The American  Stock  Exchange
under the symbol "ULB."

                                 USE OF PROCEEDS

     The Company  will  receive  the  exercise  price of the Option  Shares when
exercised by the holder thereof.  Such proceeds will be used for working capital
purposes.  The Company  will not receive any  proceeds  from the offering of the
Restricted Shares by the Selling Stockholders.
PLAN OF DISTRIBUTION

     The shares of Unilab  Common Stock covered by this Reoffer  Prospectus  are
being registered by Unilab for account of the Selling  Stockholders.  Unilab has
been  informed  by the  Selling  Stockholders  that none of such  shares will be
offered through underwriters.

     The  shares of Unilab  Common  Stock  reoffered  and  resold  hereby may be
offered  and sold from time to time by certain  stockholders  of Unilab  through
brokers on The American Stock Exchange or otherwise  (without the payment of any
underwriting  commission or discount other than normal brokers'  commissions for
effecting such transactions),  through negotiated  transactions or otherwise, at
market  prices  prevailing  at the  time of  sale,  at  prices  related  to such
prevailing  market prices or at prices  otherwise  negotiated.  To the Company's
knowledge  no specific  brokers or dealers have been  designated  by the Selling
Stockholders  nor has any  agreement  been  entered into in respect of brokerage
commissions or for the exclusive or coordinated sale of any securities which may
be reoffered pursuant to this Reoffer Prospectus.  The Selling  Stockholders and
any broker or dealer  through  whom  offers or sales of shares of Unilab  Common
Stock  covered  by  this  Reoffer   Prospectus  are  made  may  be  regarded  as
"underwriters"  within the meaning of the Act, although the Selling Stockholders
disclaim  such  status.  Compensation  received  by any such broker or dealer in
respect of the offer or sale of such  shares may be  regarded  as  underwriters'
compensation.

     All expenses of registration  incurred in connection with this offering are
being  borne by  Unilab,  but all  selling  and other  expenses  incurred  by an
individual Selling Stockholder will be borne by such Selling Stockholder.

                              SELLING STOCKHOLDERS

     This Reoffer  Prospectus relates to (i) shares of Unilab Common Stock which
have been  acquired  by certain  employees,  consultants  and  directors  of the
Company  pursuant  to the grant to such  persons of Unilab  Common  Stock  under
Restricted Stock Agreements and/or employment agreements,  (ii) shares of Unilab
Common  Stock  which may be  acquired by an employee of the Company who could be
deemed to be an  "affiliate"  of Unilab,  pursuant  to the  exercise  of options
granted to such employee under a Nonqualified  Stock Option  Agreement and (iii)
shares of Unilab Common Stock which have been acquired by a certain  director of
the Company pursuant to the 1997 Unilab Director Stock Purchase Plan.

     The  following  table  sets  forth  certain  information  known  to  Unilab
regarding the  beneficial  ownership of Unilab Common Stock as of August 1, 1997
with respect to each of the Selling Stockholders.  For purposes of this table, a
person is deemed to have "beneficial ownership" of any shares as of a given date
which such person has the right to acquire  within 60 days after such date.  For
purposes of computing the percentage of  outstanding  shares held by each person
named below on a given  date,  any  security  which such person has the right to
acquire within 60 days after such date is deemed to be  outstanding,  but is not
deemed to be outstanding  for the purpose of computing the percentage  ownership
of any other  person.  Except as noted  below,  each  person has full voting and
investment power over the shares indicated.
Number of shares of
                         Position or Material     Common Stock                              Number of Shares of
Selling                  Relationship with        Beneficially Owned     Number of Shares   Common Stock Beneficially
Stockholder              the Company During            Prior to          of Common Stock    Owned After Completion
                         Past Three Years         Reoffering (1)          Reoffered         of the Reoffering(1)
                                                  
                                                                                                      Percentage of 
                                                                                            Number    Total Shares
                                                                                                      Outstanding
David C. Weavil           Chairman, Chief          1,371,428               1,371,428             0          *
                          Executive Officer and
                          President

Kirby L. Cramer           Director                 1,011,611                 500,000       511,611        1.3%

Todd Brett                Associate Vice               4,833                   1,500         3,333          *
                          President, Business
                          Development

Lauren Bryan              Former Divisional Vice      18,500                   1,500        17,000          *
                          President

David Filer               Vice President of           16,666                  10,000         6,666          *
                          Billing

Andrew Fischinger         Regional Medical            10,000                  10,000             0          *
                          Director

Jeff Lanzolatta           Division President         175,000                  50,000       125,000          *
 
Beverly Marquez           Regional General             4,833                   1,500         3,333          *
                          Manager

Richard A. Michaelson     Senior Vice President,     535,340                  25,000       510,340        1.3
                          Chief Financial
                          Officer and Treasurer

Andrew H. Baker           Consultant; Former       2,716,288               1,033,333     1,682,955        4.2
                          Chairman, Chief
                          Executive Officer and
                          President
------------------------
*  Less than 1%.

(1)  Calculated  pursuant to Rule 13d-3  promulgated under the Exchange Act, and
     based on 40,263,977  shares of Unilab Common Stock outstanding as of August
     1, 1997.  Since the shares  being  reoffered  hereby  have been  registered
     pursuant  to Rule 415  under  the  Securities  Act and not  pursuant  to an
     underwritten  public offering,  the number of registered  shares to be sold
     pursuant hereto and the dates of such sale are not presently determinable.

     On August 4, 1997 the closing  sales  price per share of the Unilab  Common
     Stock, as reported on the American Stock Exchange was $1.375.
DOCUMENTS INCORPORATED BY REFERENCE

     The  following   documents   previously  filed  with  the  Commission  (the
"Commission")  by the Company pursuant to the Securities Act or the Exchange Act
are incorporated by reference herein and made a part hereof:

     1. The Company's  Annual  Report on Form 10-K,  as amended,  for the fiscal
year ended December 31, 1996.

     2.   The Company's Quarterly Reports on Form 10-Q for the periods ended
March 31, 1997 and June 30, 1997.

     3.   The Registrant's Current Report on Form 8-K, dated January 20, 1997

     4. The description of the Company's  Common Stock, par value $.01 per share
(the "Unilab Common Stock"),  contained in the Company's  Registration Statement
on Form 8-A filed with the Commission on June 19, 1996, including any amendments
or reports filed for the purpose of updating such description.

     All documents filed with the Commission by the Company pursuant to Sections
13(a),  13(c),  14 and  15(d)  of the 1934  Act  subsequent  to the date of this
Registration  Statement  and prior to the filing of a  post-effective  amendment
which  indicates  that all  securities  offered  herein  have been sold or which
deregisters  all  securities  then  remaining  unsold  shall  be  deemed  to  be
incorporated  by reference into this Reoffer  Prospectus and to be a part hereof
from the date of filing of such documents.

     Any statement  contained herein or in a document  incorporated or deemed to
be incorporated by reference herein shall be deemed to be modified or superseded
for purposes  hereof to the extent that a statement  contained  herein or in any
other  subsequently  filed document which is also  incorporated  or deemed to be
incorporated herein modifies or supersedes such statement. Any such statement so
modified or superseded shall not be deemed, except as so modified or superseded,
to constitute a part of this Reoffer Prospectus.

     A copy of any  documents  incorporated  by  reference  in the  Registration
Statement (not including  exhibits to the  information  that is  incorporated by
reference unless such exhibits are  specifically  incorporated by reference into
the information  that the  Registration  Statement  incorporates)  of which this
Reoffer  Prospectus  forms a part but which is not  delivered  with this Reoffer
Prospectus  will be provided by the Company without charge to any person to whom
this Reoffer Prospectus has been delivered,  upon the oral or written request of
such person.  Such requests  should be directed to Mark L. Bibi, Vice President,
Secretary and General Counsel,  Unilab  Corporation,  401 Hackensack Avenue, 9th
Floor, Hackensack, New Jersey 07601, telephone number (201) 525-1000.

                         ACCOUNTING AND AUDITING EXPERTS

     The audited Financial Statements and schedules of the Company, incorporated
by reference  in this  Reoffer  Prospectus  and  elsewhere in this  Registration
Statement  have  been  audited  by  Arthur  Andersen  LLP,   independent  public
accountants,  as  indicated  in their  reports  with  respect  thereto,  and are
incorporated by reference  herein in reliance upon the authority of said firm as
experts in accounting and auditing in giving said reports.

                                  LEGAL MATTERS

     Certain legal matters with respect to the Common Stock being offered hereby
are being passed upon by Mark L. Bibi,  Vice  President,  Secretary  and General
Counsel to the Company.
INDEMNIFICATION

     Section 145 of the General  Corporation  Law of the State of Delaware  (the
"DGCL")  provides that a Delaware  corporation  may indemnify any person against
expenses,  judgments,  fines  and  amounts  paid  in  settlements  actually  and
reasonably incurred by any such person in connection with a threatened,  pending
or completed action, suit or proceeding in which he is involved by reason of the
fact  that  he  is or  was a  director,  officer,  employee  or  agent  of  such
corporation,  or is or was  serving  at the  request  of the  corporation,  as a
director, officer, employee or agent of another corporation,  partnership, joint
venture, trust or other enterprise, provided that (i) he acted in good faith and
in a manner he reasonably believed to be in or not opposed to the best interests
of the  corporation  and (ii) with respect to any criminal action or proceeding,
he had no reasonable cause to believe his conduct was unlawful. If the action or
suit is by or in the name of the corporation,  the corporation may indemnify any
such  person  against  expenses  actually  and  reasonably  incurred  by  him in
connection  with the defense or settlement of such action of suit if he acted in
good faith and in a manner he reasonably believed to be in or not opposed to the
best interests of the corporation, except that no indemnification may be made in
respect of any claim,  issue or matter as to which such  person  shall have been
adjudged to be liable to the corporation, unless and only to the extent that the
Delaware  Court of  Chancery or the court in which the action or suit is brought
determines upon application  that,  despite the adjudication of liability but in
the light of the circumstances of the case, such person is fairly and reasonably
entitled to indemnity for such expenses as the court deems proper.

     The Amended and Restated  Certificate of  Incorporation,  as amended,  (the
"Certificate of Incorporation") of the Company provides for indemnification,  to
the fullest extent  permitted by the provisions of the DGCL, of all persons whom
it may  indemnify  pursuant  thereto.  The  Certificate  of  Incorporation  also
provides  that the  indemnification  provided by such section shall not limit or
exclude any rights,  indemnities or limitations of liability to which any person
may be  entitled  whether as a matter of law,  under the  Amended  and  Restated
By-laws of the Company, by agreement,  vote of the stockholders or disinterested
directors of the Company or otherwise.

     In  accordance  with Section  102(b)(7)  of the DGCL,  the  Certificate  of
Incorporation  limits the personal  liability of the directors of the Company to
the fullest extent permitted by such Section 102(b)(7).

     The Company  also  maintains  standard  forms of officers'  and  directors'
liability insurance policies.

Unilab Corporation has filed with the Securities            3,004,261 Shares
and Exchange Commission, Washington, D.C., a
Registration Statement under the Securities Act of
1933, as amended, with respect to this offering.           UNILAB CORPORATION
This Reoffer Prospectus omits certain  information
contained in the Registration  Statement. The
information omitted may be obtained from the Securities
and  Exchange Commission upon payment of the regular        Common Stock,
charge therefor.                                        Par Value $.01 Per Share

                   TABLE OF CONTENTS

                                                 Page

Available Information.............................A-2         PROSPECTUS
The Company.......................................A-2
Use of Proceeds...................................A-2
Plan of Distribution..............................A-3
Selling Stockholders..............................A-3
Documents Incorporated by Reference...............A-5
Accounting and Auditing Experts...................A-5
Legal Matters.....................................A-5
Indemnification...................................A-6

                                                           August 8, 1997
SIGNATURES

The Registrant

     Pursuant to the  requirements of the Securities Act of 1933, the Registrant
certifies  that it has  reasonable  grounds to believe  that it meets all of the
requirements  for  filing  on Form S-8 and has  duly  caused  this  Registration
Statement  to be  signed  on  its  behalf  by  the  undersigned,  hereunto  duly
authorized,  in the City of Los Angeles and State of  California on this 8th day
of August, 1997.

                                     UNILAB CORPORATION

                                     By: /s/   David C. Weavil
                                     Name:    David C. Weavil
                                     Title:   Chairman of the Board, President
                                     and Chief Executive Officer
POWER OF ATTORNEY

     KNOW ALL MEN BY THESE PRESENTS,  that each person whose  signature  appears
below hereby appoints Mark L. Bibi as his true and lawful attorney-in-fact, with
full power of substitution  and  resubstitution,  for him and in his name, place
and stead, in any and all capacities,  to sign any and all amendments (including
post-effective  amendments) to this Registration  Statement and to file the same
with all exhibits  thereto and other documents in connection  therewith with the
Securities  and Exchange  Commission  granting  unto said  attorney-in-fact  and
agents,  and each of them,  full power and  authority to do and perform each and
every act and thing requisite and necessary to be done in and about the premises
as fully to all intents and  purposes as he might or could do in person,  hereby
ratifying and confirming all that said attorney-in-fact and agents, or any them,
or his substitute, may lawfully do or cause to be done by virtue hereof.

     Pursuant  to  the   requirements  of  the  Securities  Act  of  1933,  this
Registration  Statement  has been signed below by the  following  persons in the
capacities and on the dated indicated.

Signature                     Title                              Date

      /s/
------------------------
David C. Weavil               Chairman of the Board,             August 8, 1997
                              President and Chief Executive
                              Officer (principal executive
                              officer)

      /s/
------------------------
Richard A. Michaelson         Senior Vice President-Finance,
                              Treasurer and Chief Financial
                              Officer (principal financial
                              and accounting)                    August 8, 1997

      /s/
------------------------
Kirby L. Cramer               Director                           August 8, 1997

      /s/
------------------------
Michael B. Hoffman            Director                           August 8, 1997

      /s/
------------------------
Haywood D. Cochrane           Director                           August 8, 1997

      /s/
------------------------
Gabriel B. Thomas             Director                           August 8, 1997

                                 EXHIBITS INDEX

Exhibit No.     Document

  4.01        Form of Unilab Corporation 1997 Directors Stock Purchase Plan.

  4.02        Form of Restricted Stock Agreement by and between the Registrant
              and Messrs. and Mesdames Brett, Bryan, Filer, Fischinger,
              Lanzolatta and Marquez.

  4.03        Form of Stock Option Agreement by and between the Registrant and
              Richard A. Michaelson.

  4.04        Restricted Stock Agreement, dated January 20, 1997, by
              and  between  the   Registrant  and  Andrew  H.  Baker
              (Incorporated  by  reference  to Exhibit  10.18 to the
              Company's  Form 10-K for the year ended  December  31,
              1996, dated March 21, 1997).

  4.05        Amendment No. 1 to Restricted Stock Agreement, dated January 20,
              1997, by and between the Registrant and Andrew H. Baker.

  4.06        Employment  Agreement,  dated January 20, 1997, by and
              between   the   Registrant   and   David   C.   Weavil
              (Incorporated  by  reference  to Exhibit  10.12 to the
              Company's  Annual  Report  on form  10-K  for the year
              ended December 31, 1996, dated March 21, 1997).

  5.01        Opinion of Mark L. Bibi, Vice President, Secretary and
              General  Counsel  for the  Registrant,  regarding  the
              legality of Common Stock being registered.

 23.01        Consent of Arthur Andersen LLP.

 23.02        Consent of Mark L. Bibi, Esq. (included in Exhibit 5.01 hereto).

 24.01        Powers of Attorney (included on the signature pages of this
              Registration Statement).