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PROSPECTUS SUPPLEMENT                           Filed Pursuant to Rule 424(b)(4)
To Prospectus Dated July 1, 1999                      Registration No. 333-80611

                                    LSI LOGIC

                                  $345,000,000

                              LSI Logic Corporation
                 4 1/4% Convertible Subordinated Notes due 2004
                           and Shares of Common Stock

     This prospectus supplement relates to the resale by the selling
securityholders of 4 1/4% convertible subordinated notes due 2004 of LSI Logic
Corporation and the shares of common stock, par value of $0.01 per share, of LSI
Logic Corporation issuable upon the conversion of the notes.

     This prospectus supplement should be read in conjunction with the
prospectus dated July 1, 1999, and the prospectus supplements dated July 22,
1999, August 23, 1999, and October 4, 1999 which are to be delivered with this
prospectus supplement. All capitalized terms used but not defined in the
prospectus supplement shall have the meanings given them in the prospectus.

     The table below sets forth information as of the date hereof concerning
beneficial ownership of the notes of the selling securityholders as listed
below. All information concerning beneficial ownership has been furnished by the
selling securityholders.



                                                 Principal Amount                       Number of Shares
                                                     of Notes         Percentage of     of Common Stock      Percentage of
                                                Beneficially Owned        Notes         That May Be Sold      Common Stock
Name                                             That May Be Sold      Outstanding            (1)           Outstanding (2)
                                                                                                      
Allstate Insurance Company                       $  1,350,000               *                43,058                *

Boulder Capital, Inc.                              10,247,600              3.0%             326,846                *

Boulder II Limited                                  3,300,000               *               105,253                *

Goldman Sachs & Company                               300,000               *                 9,568                *

Merrill Lynch, Pierce, Fenner & Smith, Inc.           375,000               *                11,961                *

Onex Industrial Partners Limited                    9,800,000              2.8%             312,570                *

Pebble Capital, Inc.                                3,602,000              1.0%             114,885                *

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*    Less than 1%

(1)  Assumes conversion of the full amount of notes held by such holder at the
     initial conversion price of $31.353 per share; such conversion price is
     subject to adjustment as described under "Description of Notes --
     Conversion of Notes." Accordingly, the number of shares of common stock
     issuable upon conversion of the Notes may increase or decrease from time to
     time. Under the terms of the Indenture, fractional shares will not be
     issued upon conversion of the notes; cash will be paid in lieu of
     fractional shares, if any.

(2)  Computed in accordance with Rule 13d-3(d)(i) promulgated under the Exchange
     Act and based upon 148,725,266 shares of common stock outstanding as of
     November 8, 1999, treating as outstanding the number of shares of common
     stock shown as being issuable upon the assumed conversion by the named
     holder of the full amount of such holder's notes but not assuming the
     conversion of the notes of any other holder.

   2

                                ---------------

     The securities offered hereby involve a high degree of risk. See "Risk
Factors" beginning on page 7 of the prospectus.

          THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE
            SECURITIES AND EXCHANGE COMMISSION NOR HAS THE SECURITIES
              AND EXCHANGE COMMISSION OR ANY STATE SECURITIES COM-
                 MISSION PASSED UPON THE ACCURACY OR ADEQUACY OF
                   THIS PROSPECTUS. ANY REPRESENTATION TO THE
                         CONTRARY IS A CRIMINAL OFFENSE.

                                ---------------

           The date of this Prospectus Supplement is November 9,1999.