EXHIBIT 8.1
 
                  [LETTERHEAD OF GIBSON, DUNN & CRUTCHER LLP]
 
                                December 5, 1997
 
(213) 229-7000                                                     C 46196-00002
 
Burke Industries, Inc.
2250 South Tenth Street
San Jose, California 95112
 
    RE:  EXCHANGE OF 10% SENIOR SUBORDINATED NOTES DUE 2007
 
Gentlemen:
 
    We have acted as special counsel to Burke Industries, Inc., a California
corporation (the "Company"), in connection with the issuance by the Company of
$110 million principal amount of 10% Senior Notes Due 2007 (the "Exchange
Notes") issued in exchange for $110 million principal amount of the Company's
10% Senior Notes due 2007 (the "Old Notes"). The terms of the Old Notes and the
Exchange Notes are described in the Prospectus dated December 5, 1997 (the
"Prospectus") and the operative documents described therein.
 
    This opinion is based on the accuracy of the facts described and the
representations made in the Prospectus.
 
    We have made such legal and factual examinations and inquiries as we have
deemed necessary or appropriate for purposes of this opinion. We are opining
herein as to the effect on the subject transaction only of the federal income
tax laws of the United States, and we express no opinion with respect to the
applicability thereto, or the effect thereon, of other federal laws, the laws of
any other jurisdiction or as to any matters of municipal law or the laws of any
other local agencies within any state.
 
    Based on the foregoing, we hereby confirm our opinion in the Prospectus
described under the caption "Federal Income Tax Consequences."
 
    This opinion is based on various statutory provisions, regulations
promulgated thereunder and interpretations thereof by the Internal Revenue
Service and the courts having jurisdiction over such matters, all of which are
subject to change either prospectively or retroactively. Any variation or
difference in the facts from those set forth in the Prospectus or the operative
documents described therein may affect the conclusions stated herein.
 
    We hereby consent to the use of our name and our opinion under the caption
"Federal Income Tax Consequences" in the Prospectus.
 
                                          Very truly yours,
 
                                          GIBSON, DUNN & CRUTCHER LLP
 
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