<PAGE>

As filed with the Securities and Exchange Commission on February 11, 2000
                                             Registration No. 333-_____________

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-8

                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933

                              McKESSON HBOC, INC.
             (Exact name of registrant as specified in its charter)

Delaware                                       94-3207296
(State or other jurisdiction of      (I.R.S. Employer Identification No.)
incorporation or organization)

                         One Post Street
                      San Francisco, California            94104
              (Address of Principal Executive Offices)  (Zip Code)

        McKesson HBOC, Inc. 1994 Stock Option and Restricted Stock Plan
                              (Full Title of Plan)

Kristina Veaco                 Ivan D. Meyerson
Senior Counsel and             Senior Vice President,
Assistant Secretary            General Counsel and Corporate Secretary
One Post Street                One Post Street
San Francisco, CA 94104        San Francisco, CA 94104
               (Name and address of agents for service)

                    (415) 983-8300
          (Telephone number, including area code, of agents for service)

The Registration Statement shall become effective upon filing in accordance with
Rule 462 under the Securities Act of 1933.

                        CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>
Title of Securities to be    Amount to be        Proposed Maximum              Proposed Maximum           Amount of
 Registered                   Registered         Offering Price Per            Aggregate Offering       Registration Fee
                                                    Share (1)                     Price  (1)
--------------------------------------------------------------------------------------------------------------------------------
<S>                          <C>                      <C>                    <C>                          <C>
Common Stock par value
$.01 per share              12,000,000                $20.28                      $243,360,000              $64,250

--------------------------------------------------------------------------------------------------------------------------------
Rights to purchase
Preferred Stock (3)         6,000,000                 N/A                          N/A                       N/A

--------------------------------------------------------------------------------------------------------------------------------
Total Registration Fee
                            N/A                       N/A                           N/A                     $64,250
--------------------------------------------------------------------------------------------------------------------------------
</TABLE>
(1)  The price per share was calculated in accordance with Rule 457(c) and (h)
     for purposes of calculating the registration fee. The maximum aggregate
     offering price was computed by multiplying 12,000,000 shares by the average
     of the high and low price of the stock on February 9, 2000.
(2)  Associated with the Common Stock are Rights to purchase Series A Preferred
     Stock that will not be exercisable or evidenced separately from the Common
     Stock prior to the occurrence of certain events.

Pursuant to Rule 416(a) this Registration Statement also covers such
indeterminate number of additional shares of Common Stock as is necessary to
eliminate any dilutive effect of any future stock split or stock dividend.  No
additional registration fee is required.
<PAGE>

                      EXPLANATORY NOTE AND INCORPORATION
                      OF CERTAIN INFORMATION BY REFERENCE
                 PURSUANT TO GENERAL INSTRUCTION E OF FORM S-8

     The Registration Statement is being filed for the purpose of increasing the
number of securities of the same class as other securities for which
Registration Statements of the Registration on Form S-8 relating to the same
employee benefit plan are effective.

     The Registrant's Form S-8 Registration Statements filed with the Securities
and Exchange Commission on March 20, 1998 (File No. 333-48337) is hereby
incorporated by reference.

Incorporation of Certain Documents by Reference

     The following documents previously filed or to be filed by the Registrant
with the Securities and Exchange Commission are hereby incorporated by reference
in this Registration Statement:

     (a)  Annual Report on Form 10-K/A for the fiscal year ended March 31, 1999.

     (b)  Quarterly Report on Form 10-Q for the quarter ended June 30,1999.

     (c)  Quarterly Report on Form 10-Q for the quarter ended September 30,1999.

     (d)  Current Reports on Form 8-K with report dates of May 3, 1999, January
          25, 2000 and February 1, 2000.

     (e)  The description of Registrant's common stock contained in the
          Registrant's Registration Statement on Form 10 (File No. 1-13252) and
          the Rights Agreement dated as of October 21, 1994, and Amendment No. 1
          thereto dated October 19, 1998, between the Registrant and First
          Chicago Trust Company of New York, as Rights Agent, filed as Exhibits
          4.1 and 4.2, respectively, to the Registrant's Annual Report on Form
          10-K/A for the fiscal year ended March 31, 1999.

     All documents subsequently filed by the Registrant pursuant to Sections
     13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 shall be
     deemed to be incorporated by reference in this Registration Statement and
     to be part hereof from the date of filing of such documents until a post-
     effective amendment of this Registration Statement is filed which indicates
     that all securities being offered hereby have been sold or which
     deregisteres all securities then remaining unsold.
<PAGE>

PART II.  INFORMATION REQUIRED IN REGISTRATION STATEMENT

Item 8.  Exhibits

Exhibit
No.            Description
---------------------------------------------------------

4         Rights Agreement dated as of October 21, 1994 and Amendment No. 1
          thereto dated October 19, 1998 between the Registrant and First
          Chicago Trust Company of New York, as Rights Agent, filed as Exhibits
          4.1 and 4.2 respectively, to the Registrant's Annual Report on Form
          10-K/A for the fiscal year ended March 31, 1999 and incorporated
          herein by reference.

5         Opinion of Ivan D. Meyerson, Senior Vice President, General Counsel
          and Corporate Secretary of the Registrant regarding the legality of
          the securities being offered.

23.1      Consent of Ivan D. Meyerson, Senior Vice President, General Counsel
          and Corporate Secretary of the Registrant regarding the legality of
          the securities being offered.  (Included in Exhibit 5)

23.2      Consent of Deloitte & Touche LLP.

23.3      Consent of Arthur Andersen LLP.

24        Powers of Attorney pursuant to which certain officers and directors of
          the Registrant signed this Registration Statement.
<PAGE>

SIGNATURES

     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, thereunto duly
authorized, in the City of San Francisco, State of California, on the 10th day
of February, 2000.

                                         McKESSON HBOC, INC.
                                         (Registrant)



                                         /s/Ivan D. Meyerson
                                         By:  Ivan D. Meyerson
                                         Senior Vice President,
                                         General Counsel and Secretary

     Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities indicated on the 25th day of August, 1999.

Signature and Title
  *John H. Hammergren, Co-President, and Co-Chief Executive Officer and Director
          (Co-Principal Executive Officer)
  *David L. Mahoney ,Co-President, and Co-Chief Executive Officer and Director
          (Co-Principal Executive Officer)
  *Heidi E. Yodowitz, Vice President, Controller and Acting
          Chief Financial Officer
          (Principal Financial Accounting Officer)

  *Alfred C. Eckert, III, Director
  *Tully M. Friedman, Director
  *Alton F. Irby, III, Director
  *M. Christine Jacobs, Director
  *Gerald E. Mayo, Director
  *James V. Napier, Director
  *David S. Pottruck, Director
  *Carl E. Reichardt, Director
  *Alan J. Seelenfreund
           Chairman of the Board and Director
  *Jane E. Shaw, Director

*By:  /s/ Ivan D. Meyerson (Attorney-in-Fact)
          ----------------
          Ivan D. Meyerson
<PAGE>

$$target=[.exind]

                                 EXHIBIT INDEX


Exhibit
No.            Description
---------------------------------------------------------

4         Rights Agreement dated as of October 21, 1994 and Amendment No. 1
          thereto dated October 19, 1998 between the Registrant and First
          Chicago Trust Company of New York, as Rights Agent, filed as Exhibits
          4.1 and 4.2 respectively, to the Registrant's Annual Report on Form
          10-K/A for the fiscal year ended March 31, 1999 and incorporated
          herein by reference.

5         Opinion of Ivan D. Meyerson, Senior Vice President, General Counsel
          and Corporate Secretary of the Registrant regarding the legality of
          the securities being offered.

23.1      Consent of Ivan D. Meyerson, Senior Vice President, General Counsel
          and Corporate Secretary of the Registrant regarding the legality of
          the securities being offered.  (Included in Exhibit 5)

23.2      Consent of Deloitte & Touche LLP.

23.3      Consent of Arthur Andersen LLP.

24        Powers of Attorney pursuant to which certain officers and directors of
          the Registrant signed this Registration Statement.
[{"type": "S-8", "sequence": "1", "description": "MCKESSON HBOC - FORM S-8", "secsgml_size_bytes": 10470}]
{"company-data": {"conformed-name": "MCKESSON HBOC INC", "cik": "0000927653", "assigned-sic": "5122", "irs-number": "943207296", "state-of-incorporation": "DE", "fiscal-year-end": "0331"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-30224", "film-number": "536555"}, "business-address": {"street1": "ONE POST ST", "street2": "MCKESSON PLAZA", "city": "SAN FRANCISCO", "state": "CA", "zip": "94104", "phone": "4159838300"}, "mail-address": {"street1": "ONE POST ST", "city": "SAN FRANCISCO", "state": "CA", "zip": "94104"}, "former-company": [{"former-conformed-name": "MCKESSON CORP", "date-changed": "19950209"}, {"former-conformed-name": "SP VENTURES INC", "date-changed": "19940728"}]}
As filed with the Securities and Exchange Commission on February 11, 2000
                                             Registration No. 333-_____________

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-8

                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933

                              McKESSON HBOC, INC.
             (Exact name of registrant as specified in its charter)

Delaware                                       94-3207296
(State or other jurisdiction of      (I.R.S. Employer Identification No.)
incorporation or organization)

                         One Post Street
                      San Francisco, California            94104
              (Address of Principal Executive Offices)  (Zip Code)

        McKesson HBOC, Inc. 1994 Stock Option and Restricted Stock Plan
                              (Full Title of Plan)

Kristina Veaco                 Ivan D. Meyerson
Senior Counsel and             Senior Vice President,
Assistant Secretary            General Counsel and Corporate Secretary
One Post Street                One Post Street
San Francisco, CA 94104        San Francisco, CA 94104
               (Name and address of agents for service)

                    (415) 983-8300
          (Telephone number, including area code, of agents for service)

The Registration Statement shall become effective upon filing in accordance with
Rule 462 under the Securities Act of 1933.

                        CALCULATION OF REGISTRATION FEE
Title of Securities to be    Amount to be        Proposed Maximum              Proposed Maximum           Amount of
 Registered                   Registered         Offering Price Per            Aggregate Offering       Registration Fee
                                                    Share (1)                     Price  (1)
--------------------------------------------------------------------------------------------------------------------------------
Common Stock par value
$.01 per share              12,000,000                $20.28                      $243,360,000              $64,250

--------------------------------------------------------------------------------------------------------------------------------
Rights to purchase
Preferred Stock (3)         6,000,000                 N/A                          N/A                       N/A

--------------------------------------------------------------------------------------------------------------------------------
Total Registration Fee
                            N/A                       N/A                           N/A                     $64,250
--------------------------------------------------------------------------------------------------------------------------------
(1)  The price per share was calculated in accordance with Rule 457(c) and (h)
     for purposes of calculating the registration fee. The maximum aggregate
     offering price was computed by multiplying 12,000,000 shares by the average
     of the high and low price of the stock on February 9, 2000.
(2)  Associated with the Common Stock are Rights to purchase Series A Preferred
     Stock that will not be exercisable or evidenced separately from the Common
     Stock prior to the occurrence of certain events.

Pursuant to Rule 416(a) this Registration Statement also covers such
indeterminate number of additional shares of Common Stock as is necessary to
eliminate any dilutive effect of any future stock split or stock dividend.  No
additional registration fee is required.
EXPLANATORY NOTE AND INCORPORATION
                      OF CERTAIN INFORMATION BY REFERENCE
                 PURSUANT TO GENERAL INSTRUCTION E OF FORM S-8

     The Registration Statement is being filed for the purpose of increasing the
number of securities of the same class as other securities for which
Registration Statements of the Registration on Form S-8 relating to the same
employee benefit plan are effective.

     The Registrant's Form S-8 Registration Statements filed with the Securities
and Exchange Commission on March 20, 1998 (File No. 333-48337) is hereby
incorporated by reference.

Incorporation of Certain Documents by Reference

     The following documents previously filed or to be filed by the Registrant
with the Securities and Exchange Commission are hereby incorporated by reference
in this Registration Statement:

     (a)  Annual Report on Form 10-K/A for the fiscal year ended March 31, 1999.

     (b)  Quarterly Report on Form 10-Q for the quarter ended June 30,1999.

     (c)  Quarterly Report on Form 10-Q for the quarter ended September 30,1999.

     (d)  Current Reports on Form 8-K with report dates of May 3, 1999, January
          25, 2000 and February 1, 2000.

     (e)  The description of Registrant's common stock contained in the
          Registrant's Registration Statement on Form 10 (File No. 1-13252) and
          the Rights Agreement dated as of October 21, 1994, and Amendment No. 1
          thereto dated October 19, 1998, between the Registrant and First
          Chicago Trust Company of New York, as Rights Agent, filed as Exhibits
          4.1 and 4.2, respectively, to the Registrant's Annual Report on Form
          10-K/A for the fiscal year ended March 31, 1999.

     All documents subsequently filed by the Registrant pursuant to Sections
     13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 shall be
     deemed to be incorporated by reference in this Registration Statement and
     to be part hereof from the date of filing of such documents until a post-
     effective amendment of this Registration Statement is filed which indicates
     that all securities being offered hereby have been sold or which
     deregisteres all securities then remaining unsold.
PART II.  INFORMATION REQUIRED IN REGISTRATION STATEMENT

Item 8.  Exhibits

Exhibit
No.            Description
---------------------------------------------------------

4         Rights Agreement dated as of October 21, 1994 and Amendment No. 1
          thereto dated October 19, 1998 between the Registrant and First
          Chicago Trust Company of New York, as Rights Agent, filed as Exhibits
          4.1 and 4.2 respectively, to the Registrant's Annual Report on Form
          10-K/A for the fiscal year ended March 31, 1999 and incorporated
          herein by reference.

5         Opinion of Ivan D. Meyerson, Senior Vice President, General Counsel
          and Corporate Secretary of the Registrant regarding the legality of
          the securities being offered.

23.1      Consent of Ivan D. Meyerson, Senior Vice President, General Counsel
          and Corporate Secretary of the Registrant regarding the legality of
          the securities being offered.  (Included in Exhibit 5)

23.2      Consent of Deloitte & Touche LLP.

23.3      Consent of Arthur Andersen LLP.

24        Powers of Attorney pursuant to which certain officers and directors of
          the Registrant signed this Registration Statement.
SIGNATURES

     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, thereunto duly
authorized, in the City of San Francisco, State of California, on the 10th day
of February, 2000.

                                         McKESSON HBOC, INC.
                                         (Registrant)

                                         /s/Ivan D. Meyerson
                                         By:  Ivan D. Meyerson
                                         Senior Vice President,
                                         General Counsel and Secretary

     Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities indicated on the 25th day of August, 1999.

Signature and Title
  *John H. Hammergren, Co-President, and Co-Chief Executive Officer and Director
          (Co-Principal Executive Officer)
  *David L. Mahoney ,Co-President, and Co-Chief Executive Officer and Director
          (Co-Principal Executive Officer)
  *Heidi E. Yodowitz, Vice President, Controller and Acting
          Chief Financial Officer
          (Principal Financial Accounting Officer)

  *Alfred C. Eckert, III, Director
  *Tully M. Friedman, Director
  *Alton F. Irby, III, Director
  *M. Christine Jacobs, Director
  *Gerald E. Mayo, Director
  *James V. Napier, Director
  *David S. Pottruck, Director
  *Carl E. Reichardt, Director
  *Alan J. Seelenfreund
           Chairman of the Board and Director
  *Jane E. Shaw, Director

*By:  /s/ Ivan D. Meyerson (Attorney-in-Fact)
          ----------------
          Ivan D. Meyerson
$$target=[.exind]

                                 EXHIBIT INDEX

Exhibit
No.            Description
---------------------------------------------------------

4         Rights Agreement dated as of October 21, 1994 and Amendment No. 1
          thereto dated October 19, 1998 between the Registrant and First
          Chicago Trust Company of New York, as Rights Agent, filed as Exhibits
          4.1 and 4.2 respectively, to the Registrant's Annual Report on Form
          10-K/A for the fiscal year ended March 31, 1999 and incorporated
          herein by reference.

5         Opinion of Ivan D. Meyerson, Senior Vice President, General Counsel
          and Corporate Secretary of the Registrant regarding the legality of
          the securities being offered.

23.1      Consent of Ivan D. Meyerson, Senior Vice President, General Counsel
          and Corporate Secretary of the Registrant regarding the legality of
          the securities being offered.  (Included in Exhibit 5)

23.2      Consent of Deloitte & Touche LLP.

23.3      Consent of Arthur Andersen LLP.

24        Powers of Attorney pursuant to which certain officers and directors of
          the Registrant signed this Registration Statement.