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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   FORM 10-K/A
                                 AMENDMENT NO. 2

      [X]      ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE
               SECURITIES EXCHANGE ACT OF 1934

                      For the fiscal year ended December 31, 1998

      [  ]     TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D)
               OF THE SECURITIES EXCHANGE ACT OF 1934

                        Commission file number 000-21930

                          BIOSOURCE INTERNATIONAL, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

            DELAWARE                                   77-0340829
 (State or other jurisdiction of          (I.R.S. Employer Identification No.)
 incorporation  or organization)
                                 820 FLYNN ROAD
                           CAMARILLO, CALIFORNIA 93102
              (Address of principal executive offices and zip code)

                                 (805) 383-5200
              (Registrant's telephone number, including area code)

           SECURITIES REGISTERED PURSUANT TO SECTION 12(B) OF THE ACT:

                                      NONE

           SECURITIES REGISTERED PURSUANT TO SECTION 12(G) OF THE ACT:

                          Common stock, $.001 par value

                         Preferred Stock Purchase Rights

     Indicate by check mark whether the registrant: (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. Yes X    No    .
                                             ----    ----

     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any Amendment to this
Form 10-K. [ ]

     The aggregate market value of the voting stock (based on the last sale
price of such stock as reported by the National Association of Securities
Dealers Automated Quotation National Market System) held by non-affiliates of
the registrant as of March 31, 1999 was $26,317,000.

     The number of shares of the Registrant's common stock outstanding as of
March 31, 1999 was 7,181,925.

                       DOCUMENTS INCORPORATED BY REFERENCE
                                      None.
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                                                                      EXHIBIT 21

                           SUBSIDIARIES OF THE COMPANY

  NAME                                            STATE/COUNTRY OF INCORPORATION

  Keystone Laboratories, Inc......................   California
  BioSource V.I. FSC., LTD........................   U.S. Virgin Islands
  BioSource Europe, S.A...........................   Belguim
      BioSource France sarl.......................   France
      BioSource B.V...............................   Holland
      BioSource Gmbh..............................   Germany
      Medgenix Diagnostici Italia, srl............   Italy
      BioSource U.K., Ltd.........................   U.K.
  Quality Controlled Biochemicals, Inc............   Massachusetts
      Javelle, Inc................................   Massachusetts


                                     Page 2
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                                   SIGNATURES

      Pursuant to the requirements of Section 13 or 15 (d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this Report to be signed on
its behalf by the undersigned, thereunto duly authorized.

                                          BIOSOURCE INTERNATIONAL, INC.


            Date:  June 13, 2000          By:    /S/ JAMES H. CHAMBERLAIN
                                              ------------------------------
                                                James H. Chamberlain
                                                CHAIRMAN AND
                                                CHIEF EXECUTIVE OFFICER


            Date:  June 13, 2000          By:   /S/ CHARLES C. BEST
                                              -----------------------------
                                                Charles C. Best
                                                CHIEF FINANCIAL OFFICER

      In accordance with the Exchange Act, this report has been signed below by
the following person on behalf of the registrant and in the capacities and on
the date indicated:



           SIGNATURE                          TITLE                  DATE

   /S/ JAMES H. CHAMBERLAIN      Chairman, Chief Executive       June 13, 2000
------------------------------   Officer, and Director
  James H. Chamberlain

   /S/ CHARLES C. BEST           Chief Financial Officer,        June 13, 2000
------------------------------   Principal Accounting Officer
     Charles C. Best

  /S/  JEAN-PIERRE L. CONTE      Director                        June 13, 2000
------------------------------
  Jean-Pierre L. Conte

                                 Director
------------------------------
 Leonard M. Hendrickson

                                 Director
------------------------------
  David J. Moffa, Ph.D.

   /S/  JOHN R. OVERTURF, JR.    Director                        June 13, 2000
------------------------------
  John R. Overturf, Jr.

                                 Director
------------------------------
     Robert D. Weist

   /S/ ROBERT J. WELTMAN         Director                        June 13, 2000
---------------------------------
    Robert J. Weltman