As filed with the Securities and Exchange Commission on August 5, 1999
                                                   Registration No. 333-________
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                   ----------
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      Under
                           The Securities Act of 1933
                                   ----------
                               KOMAG, INCORPORATED
             (Exact name of registrant as specified in its charter)
          Delaware                                          94-2914864
(State or other jurisdiction                   (IRS Employer Identification No.)
of incorporation or organization)

                   1704 Automation Parkway, San Jose, CA 95131
               (Address of principal executive offices) (Zip Code)
                                   ----------
              KOMAG, INCORPORATED 1988 EMPLOYEE STOCK PURCHASE PLAN
             KOMAG, INCORPORATED 1997 SUPPLEMENTAL STOCK OPTION PLAN
                            (Full title of the Plan)

                                   ----------

                               STEPHEN C. JOHNSON
                      President and Chief Executive Officer
                               KOMAG, INCORPORATED
                   1704 Automation Parkway, San Jose, CA 95131
                     (Name and address of agent for service)
                                 (408) 576-2000
          (Telephone number, including area code, of agent for service)
                                   ----------
<TABLE>
                                         CALCULATION OF REGISTRATION FEE
================================================================================================================
<CAPTION>
                                                             Proposed           Proposed
   Title of                                                   Maximum            Maximum
  Securities                               Amount            Offering           Aggregate             Amount of
     to be                                  to be              Price            Offering            Registration
  Registered                             Registered(1)     per Share(2)         Price(2)                 Fee
  ----------                             -------------     ------------         --------                 ---

<S>                                       <C>                 <C>              <C>                    <C>
Common Stock, $0.01 par value             5,350,000           $3.6875          $19,728,125            $5,484.42
================================================================================================================
<FN>
(1)      This  Registration  Statement  shall also cover any  additional  shares of Common  Stock  which  become
         issuable under the Registrant's Amended and Restated 1988 Employee Stock Purchase Plan by reason of any
         stock dividend,  stock split,  recapitalization or any other similar  transaction  effected without the
         Registrant's  receipt of consideration which results in an increase in the number of outstanding shares
         of the Registrant's Common Stock.

(2)      Calculated  solely for purposes of this offering  under Rule 457(h) of the  Securities  Act of 1933, as
         amended,  on the basis of the  average  of the high and low sales  price per share of the  Registrant's
         Common Stock on August 2, 1999, as reported on the Nasdaq National Market.
</FN>
</TABLE>

<PAGE>



                                     PART II

               Information Required in the Registration Statement

Item 3.  Incorporation of Certain Documents by Reference

         Komag, Incorporated (the "Registrant") hereby incorporates by reference
into this Registration  Statement the following documents  previously filed with
the Securities and Exchange Commission (the "SEC"):

         (a)      The  Registrant's  Annual  Report on Form 10-K for the  fiscal
                  year ended January 3, 1998;

         (b)      The Registrant's  Quarterly Report on Form 10-Q for the fiscal
                  quarter ended April 4, 1999 and the fiscal  quarter ended July
                  4, 1999; and

         (c)      The  description of the  Registrant's  common stock,  which is
                  incorporated  by  reference to the  Registrant's  Registration
                  Statement on Form 8-A filed with the SEC on April 29, 1988.

         All  reports  and  definitive  proxy or  information  statements  filed
pursuant to Section 13(a),  13(c), 14 or 15(d) of the Securities Exchange Act of
1934 (the "1934 Act") after the date of this Registration Statement and prior to
the filing of a  post-effective  amendment  which  indicates that all securities
offered hereby 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 in a document  incorporated or deemed to be incorporated by
reference  herein shall be deemed to be modified or  superseded  for purposes of
this Registration  Statement to the extent that a statement  contained herein or
in any  subsequently  filed document which also is deemed to be  incorporated by
reference  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.

Item 5.  Interests of Named Experts and Counsel

         Not applicable.

Item 6.  Indemnification of Directors and Officers

         The Registrant's Restated Certificate of Incorporation provides that no
director of the Registrant will be personally liable to the Registrant or any of
its  stockholders  for monetary  damages arising from such director's  breach of
fiduciary  duty.  However,  this  provision  does not apply with  respect to any
action in which the director would be liable under Section 174 of Title 8 of the
General  Corporation  Law of  Delaware,  nor does it apply  with  respect to any
liability  resulting from any transaction in which the director (i) breached his
duty of loyalty to the Registrant or its stockholders;  (ii) did not act in good
faith or, in failing to act, did not act in good faith;  (iii) acted in a manner
involving intentional misconduct or a knowing violation of law or, in failing to
act, acted in a manner involving  intentional  misconduct or a knowing violation
of law; or (iv) derived an improper personal benefit.

         Pursuant to the  provisions  of Section 145 of the General  Corporation
Law of Delaware,  every

<PAGE>

Delaware  corporation has power to indemnify any person who was or is a party or
is threatened to be made a party to any threatened, pending or completed action,
suit or proceeding  (other than an action by or in the right of the corporation)
by reason of the fact that he is or was a director,  officer,  employee or agent
of the Registrant or of any corporation,  partnership,  joint venture,  trust or
other  enterprise for which he is or was serving in such capacity at the request
of the Registrant,  against any and all expenses,  judgments,  fines and amounts
paid in  settlement  and  reasonably  incurred  by him in  connection  with such
action,  suit or proceeding.  The power to indemnify applies only if such person
acted in good  faith and in a manner he  reasonably  believed  to be in the best
interests,  or not opposed to the best interests,  of the corporation,  and with
respect to any criminal action or proceeding, had no reasonable cause to believe
his conduct was unlawful.

         The power to indemnify such person applies to actions  brought by or in
the right of the  corporation  as well,  but only to the extent of  defense  and
settlement  expenses and not to any  satisfaction of a judgment or settlement of
the claim  itself,  and with the  further  limitation  that in such  actions  no
indemnification  shall be made in the event of any adjudication of negligence or
misconduct  on the past of such  person,  unless the court,  in its  discretion,
feels that in the light of all the circumstances indemnification should apply.

         To the extent any person referred to in the two  immediately  preceding
paragraphs is successful in the defense of the actions referred to therein, such
person is,  pursuant to Section 145 of the  Delaware  General  Corporation  Law,
entitled to indemnification as described above. Section 145 also grants power to
advance  litigation  expenses  upon  receipt  of an  undertaking  to repay  such
advances  in the event no right to  indemnification  is  subsequently  shown.  A
corporation may also obtain insurance at its expense to protect anyone who might
be indemnified, or has a right to insist on indemnification, under the statute.

         The Registrant  has entered into  indemnification  agreements  with its
then current  directors and officers  which provide for  indemnification  to the
fullest extent permitted by Delaware General  Corporation Law, including Section
145 thereof.

Item 7.  Exemption from Registration Claimed

         Not applicable.

Item 8.  Exhibits

         See exhibit index.

Item 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 Securities Act of 1933 (the "1933 Act"),  (ii) to reflect in the
prospectus  any  facts  or  events  arising  after  the  effective  date of this
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 this Registration  Statement,  and (iii) to include any
material  information  with respect to the plan of  distribution  not previously
disclosed  in  this  Registration  Statement  or any  material  change  to  such
information in this  Registration  Statement;  provided,  however,  that clauses
(1)(i) and (1)(ii) shall not apply if the information required to be included in
a post-effective  amendment by those paragraphs is contained in periodic reports
filed by the Registrant  pursuant to Section 13 or Section 15(d) of the 1934 Act
that are incorporated by reference into 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

<PAGE>

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 upon the termination of the 1988
Employee Stock Purchase Plan.

         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 that is
incorporated by reference into this 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  or  controlling  persons of the
Registrant  pursuant to the indemnity  provisions  summarized in Item 6 above or
otherwise,  the Registrant has been informed that in the opinion of the SEC such
indemnification  is against  public  policy as expressed in the 1933 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  1933  Act  and  will  be  governed  by the  final
adjudication of such issue.



<PAGE>

                                   SIGNATURES

                  Pursuant to the requirements of the Securities Act of 1933, as
amended, 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 Jose, State of California,  on this 5th day
of August, 1999.


                                      KOMAG, INCORPORATED


                                      By:______________________________________
                                        Stephen C. Johnson
                                        President  and Chief  Executive
Officer


                                POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS:

                  That  the   undersigned   officers  and  directors  of  Komag,
Incorporated,  a Delaware corporation,  do hereby constitute and appoint Stephen
C. Johnson and William L. Potts, Jr., and each of them, the lawful attorneys and
agents,  with full power and  authority to do any and all acts and things and to
execute any and all instruments which said attorneys and agents,  and any one of
them,  determine  may be  necessary  or  advisable  or  required  to enable said
corporation to comply with the Securities Act of 1933, as amended, and any rules
or regulations  or  requirements  of the  Securities and Exchange  Commission in
connection with this Registration Statement.  Without limiting the generality of
the foregoing  power and  authority,  the powers  granted  include the power and
authority to sign the names of the  undersigned  officers  and  directors in the
capacities  indicated  below  to  this  Registration  Statement,  to any and all
amendments,  both  pre-effective  and  post-effective,  and  supplements to this
Registration  Statement,  and to any and all  instruments or documents  filed as
part of or in  conjunction  with this  Registration  Statement or  amendments or
supplements  thereof,  and each of the undersigned  hereby ratifies and confirms
all that said attorneys and agents, or any of them, shall do or cause to be done
by virtue hereof. This Power of Attorney may be signed in several counterparts.

                  IN WITNESS WHEREOF,  each of the undersigned has executed this
Power of Attorney as of the date indicated.

<TABLE>
                  Pursuant to the requirements of the Securities Act of 1933, as
amended,  this  Registration  Statement  has been signed below by the  following
persons in the capacities and on the dates indicated.

<CAPTION>
Signatures                                        Title                                          Date
----------                                        -----                                          ----


<S>                                               <C>                                            <C>
--------------------------                        President, Chief Executive Officer             August 4, 1999
Stephen C. Johnson                                and Director (Principal Executive
                                                  Officer)

<PAGE>

Signatures                                        Title                                          Date
----------                                        -----                                          ----


--------------------------                        Chairman of the Board                          August 4, 1999
Tu Chen



--------------------------                        Senior Vice President,                         August 4, 1999
William L. Potts, Jr.                             Chief Financial Officer and
                                                  Secretary (Principal Financial
                                                  and Accounting Officer)



--------------------------                        Director                                       August 4, 1999
Chris A. Eyre



--------------------------                        Director                                       August 4, 1999
Irwin Federman



--------------------------                        Director                                       August 4, 1999
George A. Neil



--------------------------                        Director                                       August 4, 1999
Michael R. Splinter



--------------------------                        Director                                       August 4, 1999
Anthony Sun



--------------------------                        Director                                       August 4, 1999
Masayoshi Takebayashi

</TABLE>

<PAGE>



                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                                    EXHIBITS

                                       TO

                                    FORM S-8

                                      UNDER

                             SECURITIES ACT OF 1933


                               KOMAG, INCORPORATED



<PAGE>


                                  EXHIBIT INDEX

 Exhibit Number       Exhibit
 --------------       -------

     5.1              Opinion of Wilson Sonsini Goodrich and Rosati

    23.1              Consent of Ernst & Young LLP

    23.2              Consent of Chuo Audit Corporation

    23.3              Consent of Wilson Sonsini Goodrich and Rosati (included in
                      Exhibit 5.1)

    24                Power of Attorney (see signature page)

    99.1              Komag,  Incorporated 1988 Employee Stock Purchase Plan (as
                      amended and restated on February 4, 1999)

    99.2*             Form of Enrollment Form to be generally used in connection
                      with Komag,  Incorporated  1988  Employee  Stock  Purchase
                      Plan.

    99.3              Komag,  Incorporated 1997  Supplemental  Stock Option Plan
                      (as amended on June 12, 1998).

    99.4              Notice of Grant generally used in connection with the 1997
                      Supplemental Stock Option Plan.

    99.5              Form  of  Stock  Option   Agreement   generally   used  in
                      connection with the 1997 Supplemental Stock Option Plan.

*  Incorporated  by  reference  to  Exhibits  28.1 and  28.2,  respectively,  to
Registrant's  Registration Statement No. 33-53432 on Form S-8 filed with the SEC
on October 16, 1992 .
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 19683}]
{"company-data": {"conformed-name": "KOMAG INC /DE/", "cik": "0000813347", "assigned-sic": "3695", "irs-number": "942914864", "state-of-incorporation": "DE", "fiscal-year-end": "0103"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-84567", "film-number": "99678523"}, "business-address": {"street1": "1704 AUTOMATION PWY", "city": "SAN JOSE", "state": "CA", "zip": "95131", "phone": "4089462300"}, "mail-address": {"street1": "1704 AUTOMATION PWY", "city": "SAN JOSE", "state": "CA", "zip": "95131"}}
As filed with the Securities and Exchange Commission on August 5, 1999
                                                   Registration No. 333-________
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                   ----------
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      Under
                           The Securities Act of 1933
                                   ----------
                               KOMAG, INCORPORATED
             (Exact name of registrant as specified in its charter)
          Delaware                                          94-2914864
(State or other jurisdiction                   (IRS Employer Identification No.)
of incorporation or organization)

                   1704 Automation Parkway, San Jose, CA 95131
               (Address of principal executive offices) (Zip Code)
                                   ----------
              KOMAG, INCORPORATED 1988 EMPLOYEE STOCK PURCHASE PLAN
             KOMAG, INCORPORATED 1997 SUPPLEMENTAL STOCK OPTION PLAN
                            (Full title of the Plan)

                                   ----------

                               STEPHEN C. JOHNSON
                      President and Chief Executive Officer
                               KOMAG, INCORPORATED
                   1704 Automation Parkway, San Jose, CA 95131
                     (Name and address of agent for service)
                                 (408) 576-2000
          (Telephone number, including area code, of agent for service)
                                   ----------

                                         CALCULATION OF REGISTRATION FEE
================================================================================================================
Proposed           Proposed
   Title of                                                   Maximum            Maximum
  Securities                               Amount            Offering           Aggregate             Amount of
     to be                                  to be              Price            Offering            Registration
  Registered                             Registered(1)     per Share(2)         Price(2)                 Fee
  ----------                             -------------     ------------         --------                 ---
Common Stock, $0.01 par value             5,350,000           $3.6875          $19,728,125            $5,484.42
================================================================================================================
(1)      This  Registration  Statement  shall also cover any  additional  shares of Common  Stock  which  become
         issuable under the Registrant's Amended and Restated 1988 Employee Stock Purchase Plan by reason of any
         stock dividend,  stock split,  recapitalization or any other similar  transaction  effected without the
         Registrant's  receipt of consideration which results in an increase in the number of outstanding shares
         of the Registrant's Common Stock.

(2)      Calculated  solely for purposes of this offering  under Rule 457(h) of the  Securities  Act of 1933, as
         amended,  on the basis of the  average  of the high and low sales  price per share of the  Registrant's
         Common Stock on August 2, 1999, as reported on the Nasdaq National Market.
PART II

               Information Required in the Registration Statement

Item 3.  Incorporation of Certain Documents by Reference

         Komag, Incorporated (the "Registrant") hereby incorporates by reference
into this Registration  Statement the following documents  previously filed with
the Securities and Exchange Commission (the "SEC"):

         (a)      The  Registrant's  Annual  Report on Form 10-K for the  fiscal
                  year ended January 3, 1998;

         (b)      The Registrant's  Quarterly Report on Form 10-Q for the fiscal
                  quarter ended April 4, 1999 and the fiscal  quarter ended July
                  4, 1999; and

         (c)      The  description of the  Registrant's  common stock,  which is
                  incorporated  by  reference to the  Registrant's  Registration
                  Statement on Form 8-A filed with the SEC on April 29, 1988.

         All  reports  and  definitive  proxy or  information  statements  filed
pursuant to Section 13(a),  13(c), 14 or 15(d) of the Securities Exchange Act of
1934 (the "1934 Act") after the date of this Registration Statement and prior to
the filing of a  post-effective  amendment  which  indicates that all securities
offered hereby 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 in a document  incorporated or deemed to be incorporated by
reference  herein shall be deemed to be modified or  superseded  for purposes of
this Registration  Statement to the extent that a statement  contained herein or
in any  subsequently  filed document which also is deemed to be  incorporated by
reference  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.

Item 5.  Interests of Named Experts and Counsel

         Not applicable.

Item 6.  Indemnification of Directors and Officers

         The Registrant's Restated Certificate of Incorporation provides that no
director of the Registrant will be personally liable to the Registrant or any of
its  stockholders  for monetary  damages arising from such director's  breach of
fiduciary  duty.  However,  this  provision  does not apply with  respect to any
action in which the director would be liable under Section 174 of Title 8 of the
General  Corporation  Law of  Delaware,  nor does it apply  with  respect to any
liability  resulting from any transaction in which the director (i) breached his
duty of loyalty to the Registrant or its stockholders;  (ii) did not act in good
faith or, in failing to act, did not act in good faith;  (iii) acted in a manner
involving intentional misconduct or a knowing violation of law or, in failing to
act, acted in a manner involving  intentional  misconduct or a knowing violation
of law; or (iv) derived an improper personal benefit.

         Pursuant to the  provisions  of Section 145 of the General  Corporation
Law of Delaware,  every
Delaware  corporation has power to indemnify any person who was or is a party or
is threatened to be made a party to any threatened, pending or completed action,
suit or proceeding  (other than an action by or in the right of the corporation)
by reason of the fact that he is or was a director,  officer,  employee or agent
of the Registrant or of any corporation,  partnership,  joint venture,  trust or
other  enterprise for which he is or was serving in such capacity at the request
of the Registrant,  against any and all expenses,  judgments,  fines and amounts
paid in  settlement  and  reasonably  incurred  by him in  connection  with such
action,  suit or proceeding.  The power to indemnify applies only if such person
acted in good  faith and in a manner he  reasonably  believed  to be in the best
interests,  or not opposed to the best interests,  of the corporation,  and with
respect to any criminal action or proceeding, had no reasonable cause to believe
his conduct was unlawful.

         The power to indemnify such person applies to actions  brought by or in
the right of the  corporation  as well,  but only to the extent of  defense  and
settlement  expenses and not to any  satisfaction of a judgment or settlement of
the claim  itself,  and with the  further  limitation  that in such  actions  no
indemnification  shall be made in the event of any adjudication of negligence or
misconduct  on the past of such  person,  unless the court,  in its  discretion,
feels that in the light of all the circumstances indemnification should apply.

         To the extent any person referred to in the two  immediately  preceding
paragraphs is successful in the defense of the actions referred to therein, such
person is,  pursuant to Section 145 of the  Delaware  General  Corporation  Law,
entitled to indemnification as described above. Section 145 also grants power to
advance  litigation  expenses  upon  receipt  of an  undertaking  to repay  such
advances  in the event no right to  indemnification  is  subsequently  shown.  A
corporation may also obtain insurance at its expense to protect anyone who might
be indemnified, or has a right to insist on indemnification, under the statute.

         The Registrant  has entered into  indemnification  agreements  with its
then current  directors and officers  which provide for  indemnification  to the
fullest extent permitted by Delaware General  Corporation Law, including Section
145 thereof.

Item 7.  Exemption from Registration Claimed

         Not applicable.

Item 8.  Exhibits

         See exhibit index.

Item 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 Securities Act of 1933 (the "1933 Act"),  (ii) to reflect in the
prospectus  any  facts  or  events  arising  after  the  effective  date of this
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 this Registration  Statement,  and (iii) to include any
material  information  with respect to the plan of  distribution  not previously
disclosed  in  this  Registration  Statement  or any  material  change  to  such
information in this  Registration  Statement;  provided,  however,  that clauses
(1)(i) and (1)(ii) shall not apply if the information required to be included in
a post-effective  amendment by those paragraphs is contained in periodic reports
filed by the Registrant  pursuant to Section 13 or Section 15(d) of the 1934 Act
that are incorporated by reference into 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 upon the termination of the 1988
Employee Stock Purchase Plan.

         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 that is
incorporated by reference into this 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  or  controlling  persons of the
Registrant  pursuant to the indemnity  provisions  summarized in Item 6 above or
otherwise,  the Registrant has been informed that in the opinion of the SEC such
indemnification  is against  public  policy as expressed in the 1933 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  1933  Act  and  will  be  governed  by the  final
adjudication of such issue.
SIGNATURES

                  Pursuant to the requirements of the Securities Act of 1933, as
amended, 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 Jose, State of California,  on this 5th day
of August, 1999.

                                      KOMAG, INCORPORATED

                                      By:______________________________________
                                        Stephen C. Johnson
                                        President  and Chief  Executive
Officer

                                POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS:

                  That  the   undersigned   officers  and  directors  of  Komag,
Incorporated,  a Delaware corporation,  do hereby constitute and appoint Stephen
C. Johnson and William L. Potts, Jr., and each of them, the lawful attorneys and
agents,  with full power and  authority to do any and all acts and things and to
execute any and all instruments which said attorneys and agents,  and any one of
them,  determine  may be  necessary  or  advisable  or  required  to enable said
corporation to comply with the Securities Act of 1933, as amended, and any rules
or regulations  or  requirements  of the  Securities and Exchange  Commission in
connection with this Registration Statement.  Without limiting the generality of
the foregoing  power and  authority,  the powers  granted  include the power and
authority to sign the names of the  undersigned  officers  and  directors in the
capacities  indicated  below  to  this  Registration  Statement,  to any and all
amendments,  both  pre-effective  and  post-effective,  and  supplements to this
Registration  Statement,  and to any and all  instruments or documents  filed as
part of or in  conjunction  with this  Registration  Statement or  amendments or
supplements  thereof,  and each of the undersigned  hereby ratifies and confirms
all that said attorneys and agents, or any of them, shall do or cause to be done
by virtue hereof. This Power of Attorney may be signed in several counterparts.

                  IN WITNESS WHEREOF,  each of the undersigned has executed this
Power of Attorney as of the date indicated.

                  Pursuant to the requirements of the Securities Act of 1933, as
amended,  this  Registration  Statement  has been signed below by the  following
persons in the capacities and on the dates indicated.
Signatures                                        Title                                          Date
----------                                        -----                                          ----
--------------------------                        President, Chief Executive Officer             August 4, 1999
Stephen C. Johnson                                and Director (Principal Executive
                                                  Officer)
Signatures                                        Title                                          Date
----------                                        -----                                          ----

--------------------------                        Chairman of the Board                          August 4, 1999
Tu Chen

--------------------------                        Senior Vice President,                         August 4, 1999
William L. Potts, Jr.                             Chief Financial Officer and
                                                  Secretary (Principal Financial
                                                  and Accounting Officer)

--------------------------                        Director                                       August 4, 1999
Chris A. Eyre

--------------------------                        Director                                       August 4, 1999
Irwin Federman

--------------------------                        Director                                       August 4, 1999
George A. Neil

--------------------------                        Director                                       August 4, 1999
Michael R. Splinter

--------------------------                        Director                                       August 4, 1999
Anthony Sun

--------------------------                        Director                                       August 4, 1999
Masayoshi Takebayashi
SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    EXHIBITS

                                       TO

                                    FORM S-8

                                      UNDER

                             SECURITIES ACT OF 1933

                               KOMAG, INCORPORATED
EXHIBIT INDEX

 Exhibit Number       Exhibit
 --------------       -------

     5.1              Opinion of Wilson Sonsini Goodrich and Rosati

    23.1              Consent of Ernst & Young LLP

    23.2              Consent of Chuo Audit Corporation

    23.3              Consent of Wilson Sonsini Goodrich and Rosati (included in
                      Exhibit 5.1)

    24                Power of Attorney (see signature page)

    99.1              Komag,  Incorporated 1988 Employee Stock Purchase Plan (as
                      amended and restated on February 4, 1999)

    99.2*             Form of Enrollment Form to be generally used in connection
                      with Komag,  Incorporated  1988  Employee  Stock  Purchase
                      Plan.

    99.3              Komag,  Incorporated 1997  Supplemental  Stock Option Plan
                      (as amended on June 12, 1998).

    99.4              Notice of Grant generally used in connection with the 1997
                      Supplemental Stock Option Plan.

    99.5              Form  of  Stock  Option   Agreement   generally   used  in
                      connection with the 1997 Supplemental Stock Option Plan.

*  Incorporated  by  reference  to  Exhibits  28.1 and  28.2,  respectively,  to
Registrant's  Registration Statement No. 33-53432 on Form S-8 filed with the SEC
on October 16, 1992 .