As filed with the Securities and Exchange Commission on March 30, 1998

                                                           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

                       1997 SUPPLEMENTAL STOCK OPTION PLAN
                            (Full title of the Plan)

                               STEPHEN C. JOHNSON
                      President and Chief Executive Officer
                   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>
<CAPTION>
                         CALCULATION OF REGISTRATION FEE
================================================================================================================
<S>                               <C>                     <C>                 <C>                  <C>
                                                             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                  Fee
  ----------                      --------------           -------------        ---------           ------------

Common Stock,                       4,600,000                 $15.22           $70,012,000           $20,653.54
$0.01 par value

================================================================================================================
<FN>
(1)     This  Registration  Statement shall also cover any additional  shares of
        Common Stock which become  issuable  under the 1997  Supplemental  Stock
        Option   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 Registrant's outstanding shares of 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 selling  prices per share of  Registrant's  Common Stock on
        March 24, 1998, as reported on the Nasdaq National Market.
</FN>
</TABLE>



<PAGE>

                                     PART II

               Information Required in the Registration Statement

Item 3.  Incorporation of 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  December  28, 1997 filed with the SEC on March 25,
                  1998.

         b.       The  Registrant's  Registration  Statement No. 0-16852 on Form
                  8-A  filed  with the SEC on April 29,  1988 in which  there is
                  described the terms,  rights and provisions  applicable to the
                  Registrant's outstanding Common Stock.

                  All reports and definitive proxy or information  statements of
Registrant 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 the 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.



<PAGE>

         The power to indemnify 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
unless  the  court,  in its  discretion,  feels  that  in the  light  of all the
circumstances indemnification should apply.

         To the extent any of the  persons  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

 Exhibit Number       Exhibit

    4                 Instruments Defining Rights of Stockholders.  Reference is
                      made to Registrant's Registration Statement No. 0-16852 on
                      Form  8-A  which  is  incorporated   herein  by  reference
                      pursuant to Item 3(b).

    5                 Opinion and Consent of Brobeck, Phleger & Harrison LLP.

    23.1              Consent of Independent Auditors - Ernst & Young LLP.

    23.2              Consent of  Brobeck,  Phleger & Harrison is  contained  in
                      Exhibit 5.

    24                Power of Attorney.  Reference is made to page II-4 of this
                      Registration Statement.

    99.1              Komag, Inc. Supplemental Stock Option Plan.

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

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

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 Registrant's 1997  Supplemental  Stock Option
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 the Registration Statement shall
be deemed to be a new registration  statement relating to the

<PAGE>

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  provisions  summarized in Item 6 or
otherwise,  the  Registrant  has  been  informed  that,  in the  opinion  of the
Securities  and Exchange  Commission,  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 26th day of March, 1998.


                             Komag, Incorporated

                             By _______________________________________________
                                Stephen C. Johnson
                                President, Chief Executive Officer and Director



                                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  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                           March 26, 1998
---------------------------         and Director (Principal Executive Officer)
Stephen C. Johnson


                                    Chairman of the Board                                        March 30, 1998
---------------------------
Tu Chen



                                    Senior Vice President of Finance,                            March 26, 1998
---------------------------         Chief Financial Officer and
William L. Potts, Jr.               Secretary (Principal Financial
                                    and Accounting Officer)

<PAGE>
Signatures                                        Title                                                Date
----------                                        -----                                                ----

----------------                                  Director                                       March 27, 1998
Craig R. Barrett


-------------                                     Director                                       March 27, 1998
Chris A. Eyre


--------------                                    Director                                       March 27, 1998
Irwin Federman


--------------                                    Director                                       March 27, 1998
George A. Neil


------------                                      Director                                       March 27, 1998
Max Palevsky


-----------                                       Director                                       March 27, 1998
Anthony Sun


---------------------                             Director                                       March 27, 1998
Masayoshi Takebayashi

</TABLE>



<PAGE>



                       SECURITIES AND EXCHANGE COMMISSION
                                WASHINGTON, D.C.


                                    EXHIBITS

                                       TO

                                    FORM S-8

                                      UNDER

                             SECURITIES ACT OF 1933


                               KOMAG, INCORPORATED




<PAGE>

                                  EXHIBIT INDEX


Exhibit Number                       Exhibit

    4              Instruments  Defining  Rights of  Stockholders.  Reference is
                   made to  Registrant's  Registration  Statement No. 0-16852 on
                   Form 8-A which is incorporated  herein by reference  pursuant
                   to Item 3(b).

    5              Opinion and Consent of Brobeck, Phleger & Harrison LLP.

    23.1           Consent of Independent Auditors - Ernst & Young LLP.

    23.2           Consent of Brobeck,  Phleger & Harrison  LLP is  contained in
                   Exhibit 5.

    24             Power of  Attorney.  Reference  is made to page  II-4 of this
                   Registration Statement.

    99.1           Komag, Inc. Supplemental Stock Option Plan.

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

    99.399.3       Form of Stock Option  Agreement  generally used in connection
                   with the 1997 Supplemental Stock Option Plan.
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 20283}]
{"company-data": {"conformed-name": "KOMAG INC /DE/", "cik": "0000813347", "assigned-sic": "3695", "irs-number": "942914864", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-48867", "film-number": "98578707"}, "business-address": {"street1": "1704 AUTOMATION PWY", "city": "SAN JOSE", "state": "CA", "zip": "95131", "phone": "4089462300"}, "mail-address": {"street1": "275 S HILLVIEW DR", "city": "MILPITAS", "state": "CA", "zip": "95035"}}
As filed with the Securities and Exchange Commission on March 30, 1998

                                                           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

                       1997 SUPPLEMENTAL STOCK OPTION PLAN
                            (Full title of the Plan)

                               STEPHEN C. JOHNSON
                      President and Chief Executive Officer
                   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                  Fee
  ----------                      --------------           -------------        ---------           ------------

Common Stock,                       4,600,000                 $15.22           $70,012,000           $20,653.54
$0.01 par value

================================================================================================================
(1)     This  Registration  Statement shall also cover any additional  shares of
        Common Stock which become  issuable  under the 1997  Supplemental  Stock
        Option   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 Registrant's outstanding shares of 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 selling  prices per share of  Registrant's  Common Stock on
        March 24, 1998, as reported on the Nasdaq National Market.
PART II

               Information Required in the Registration Statement

Item 3.  Incorporation of 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  December  28, 1997 filed with the SEC on March 25,
                  1998.

         b.       The  Registrant's  Registration  Statement No. 0-16852 on Form
                  8-A  filed  with the SEC on April 29,  1988 in which  there is
                  described the terms,  rights and provisions  applicable to the
                  Registrant's outstanding Common Stock.

                  All reports and definitive proxy or information  statements of
Registrant 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 the 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 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
unless  the  court,  in its  discretion,  feels  that  in the  light  of all the
circumstances indemnification should apply.

         To the extent any of the  persons  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

 Exhibit Number       Exhibit

    4                 Instruments Defining Rights of Stockholders.  Reference is
                      made to Registrant's Registration Statement No. 0-16852 on
                      Form  8-A  which  is  incorporated   herein  by  reference
                      pursuant to Item 3(b).

    5                 Opinion and Consent of Brobeck, Phleger & Harrison LLP.

    23.1              Consent of Independent Auditors - Ernst & Young LLP.

    23.2              Consent of  Brobeck,  Phleger & Harrison is  contained  in
                      Exhibit 5.

    24                Power of Attorney.  Reference is made to page II-4 of this
                      Registration Statement.

    99.1              Komag, Inc. Supplemental Stock Option Plan.

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

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

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 Registrant's 1997  Supplemental  Stock Option
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 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  or  controlling
persons of the  Registrant  pursuant to the  provisions  summarized in Item 6 or
otherwise,  the  Registrant  has  been  informed  that,  in the  opinion  of the
Securities  and Exchange  Commission,  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 26th day of March, 1998.

                             Komag, Incorporated

                             By _______________________________________________
                                Stephen C. Johnson
                                President, Chief Executive Officer and Director

                                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  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                           March 26, 1998
---------------------------         and Director (Principal Executive Officer)
Stephen C. Johnson

                                    Chairman of the Board                                        March 30, 1998
---------------------------
Tu Chen

                                    Senior Vice President of Finance,                            March 26, 1998
---------------------------         Chief Financial Officer and
William L. Potts, Jr.               Secretary (Principal Financial
                                    and Accounting Officer)
Signatures                                        Title                                                Date
----------                                        -----                                                ----

----------------                                  Director                                       March 27, 1998
Craig R. Barrett

-------------                                     Director                                       March 27, 1998
Chris A. Eyre

--------------                                    Director                                       March 27, 1998
Irwin Federman

--------------                                    Director                                       March 27, 1998
George A. Neil

------------                                      Director                                       March 27, 1998
Max Palevsky

-----------                                       Director                                       March 27, 1998
Anthony Sun

---------------------                             Director                                       March 27, 1998
Masayoshi Takebayashi
SECURITIES AND EXCHANGE COMMISSION
                                WASHINGTON, D.C.

                                    EXHIBITS

                                       TO

                                    FORM S-8

                                      UNDER

                             SECURITIES ACT OF 1933

                               KOMAG, INCORPORATED
EXHIBIT INDEX

Exhibit Number                       Exhibit

    4              Instruments  Defining  Rights of  Stockholders.  Reference is
                   made to  Registrant's  Registration  Statement No. 0-16852 on
                   Form 8-A which is incorporated  herein by reference  pursuant
                   to Item 3(b).

    5              Opinion and Consent of Brobeck, Phleger & Harrison LLP.

    23.1           Consent of Independent Auditors - Ernst & Young LLP.

    23.2           Consent of Brobeck,  Phleger & Harrison  LLP is  contained in
                   Exhibit 5.

    24             Power of  Attorney.  Reference  is made to page  II-4 of this
                   Registration Statement.

    99.1           Komag, Inc. Supplemental Stock Option Plan.

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

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