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                                                                    EXHIBIT 23.1

               CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

               We consent to the reference to our firm under the captions
"Selected Consolidated Financial Data" and "Experts" in the Registration
Statement on Form S-4 and the Registration Statement on Form S-3 and related
Prospectus of Komag, Incorporated for the offer to exchange Convertible
Subordinated Notes and to the incorporation by reference therein of our report
dated January 29, 2001, with respect to the consolidated financial statements
and schedule of Komag, Incorporated included in its Annual Report (Form 10-K)
for the year ended December 31, 2000, filed with the Securities and Exchange
Commission.



                                            /s/ Ernst & Young LLP



San Jose, California
April 4, 2001