FOR IMMEDIATE RELEASE


        Bio-Rad Laboratories Reports Second-Quarter Financial Results


     HERCULES, CA - August 5, 2004 - Bio-Rad Laboratories, Inc. (AMEX:
     BIO and BIOb), a multinational manufacturer and distributor of life
     science research products and clinical diagnostics, announced
     financial results today for the second quarter ended June 30, 2004.
     Second quarter net sales from continuing operations were $260.5
     million, up 8.9 percent compared to the $239.3 million reported for
     the same quarter of 2003.  This increase was primarily the result
     of organic growth in the Company's main business segments as well
     as currency effects.  For the quarter, income from continuing
     operations was $20.3 million compared to $21.9 million in the
     second quarter of last year.

     In May, the Company sold its U.K. based confocal microscopy product
     line to Carl Zeiss Jena GMBH.  As required by SFAS 144, the sales
     and expenses related to this product line for current and prior
     periods have been reclassified to a separate line on the income
     statement titled "Discontinued operations."

     Net sales for the first half of 2004 grew by 9.1 percent to $523.3
     million compared to the same period last year.  At 57.1 percent,
     gross margin for the first half of 2004 was down slightly compared
     to 57.5 percent in the same period of 2003.  However, at 57.4
     percent, second-quarter gross margin was markedly higher than the
     56.4 percent reported for the second quarter of 2003.  This
     improvement was a result of the Company's product mix skewing
     toward consumables as well as the elimination of some low margin
     products.  Income from continuing operations for the six-month
     period was $42.9 million, or $1.67 per share, an 11.8 percent
     decrease compared to the $48.6 million, or $1.92 per share,
     reported in the corresponding period of last year.  This reduction
     was largely due to anticipated spending on infrastructure
     improvements.

     Second Quarter Highlights
     -    Overall net sales for the second quarter grew by 8.9 percent
       to reach $260.5 million compared to $239.3 million reported in the
       second quarter of 2003.  On a currency-neutral basis, revenues were
       up 4.2 percent versus second-quarter 2003 results.
     -    Basic earnings from continuing operations were $0.79 per
       share, or $0.76 per share on a diluted basis, compared to basic
       earnings per share of $0.86 and diluted earnings per share of $0.83
       in the same period of 2003.
     -    Life Science segment net sales for the quarter were $113.9
     million, 3.4 percent higher than the comparable period last year.
     On a currency neutral basis, segment sales declined by 1.3 percent
     for the quarter.  Overall performance in the Life Science segment
     was negatively impacted by increased competition in certain
     instrumentation businesses and the timing of shipments in the
     process chromatography business.  Solid performers in this segment
     included the multiplex protein array technology, amplification
     reagents, and electrophoresis product lines.
                                   (more)
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     Bio-Rad Reports Second Quarter 2004
     Page 2


     -    The Clinical Diagnostics segment reported net sales of $144.4
       million for the quarter, up 13.4 percent compared to the second
       quarter of 2003, or 8.8 percent excluding currency effects.  These
       results were the result of growth in several areas including
       autoimmune testing, quality-control management and diabetes
       monitoring, as well as the addition of acquired Hematronix products
       to the quality controls portfolio.  Moreover, sales of Bio-Rad's
       Platelia(TM) Aspergillus EIA test kit in the United States and Canada
       gained momentum, in part due to the Company's co-marketing
       agreement with Enzon Pharmaceuticals, Inc.
     -    During the quarter, the Company granted a worldwide, non-
     exclusive sublicense to OraSure Technologies, Inc. under patents
     relating to the Human Immunodeficiency Virus, Type 2, or HIV-2.

     "While our life science market is experiencing modest growth to
     date, we are anticipating the introduction of several very
     interesting new products in the coming months," said Norman
     Schwartz, President and Chief Executive Officer.  "This, coupled
     with the recent introduction of the Bio-Plex(TM) 2200 to the
     diagnostic market, should provide good momentum during the second
     half of the year."

     Management will discuss these results in a conference call at 2:00
     p.m. PT (5:00 p.m. ET) August 5, 2004. Interested parties can
     access the call by dialing (800) 901-5218 (in the U.S.), or (617)
     786-4511 (international), access number 89936051.  The live web
     cast can be accessed at http://www.bio-rad.com.  A replay of the
     call will be available at (888) 286-8010 (in the U.S.), or (617)
     801-6888 (international), access number 73327988, for seven days
     following the call and the web cast can be accessed at
     http://www.bio-rad.com for 30 days.

     Bio-Rad Laboratories, Inc. is a multinational manufacturer and
     distributor of life science research products and clinical
     diagnostics.  It is based in Hercules, California, and serves more
     than 70,000 research and industry customers worldwide through a
     network of more than 30 wholly owned subsidiary offices.

     Various statements made within this press release may constitute
     "forward-looking statements" for purposes of the Securities and
     Exchange Commission's "safe harbor" provisions under the Private
     Securities Litigation Reform Act of 1995 and Rule 3b-6 under the
     Securities Exchange Act of 1934. The forward-looking statements
     contained herein involve risks and uncertainties that could cause
     results to differ materially from the Company's expectations.

     For more information contact:
     Christine Tsingos, Vice President and Chief Financial Officer, or
     Ron Hutton, Treasurer
     Bio-Rad Laboratories, Inc.
     Phone:  (510) 724-7000
     E-mail:  investor_relations@bio-rad.com
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                     Bio-Rad Laboratories, Inc.
                         Second Quarter 2004
             Condensed Consolidated Statements of Income

                (In thousands, except per share data)
                             (UNAUDITED)






                                      Three Months Ended    Six Months Ended
                                            June 30,            June 30,

                                       2004       2003       2004       2003
                                     --------   --------   --------   --------
 Net sales                           $260,546   $239,325   $523,295   $479,723
 Cost of goods sold                   110,885    104,265    224,370    203,985
                                     --------   --------   --------   --------
 Gross profit                         149,661    135,060    298,925    275,738

 Selling, general and
   administrative expense              90,199     76,947    177,256    152,269
 Product research and
   development expense                 25,545     21,990     49,878     42,601
 Purchased in-process research
   and development expense                  -          -        900          -
 Interest expense                       4,919      3,696      9,969      8,347
 Foreign exchange losses, net             545        554        747      1,323
 Other (income) expense, net             (866)      (880)      (650)    (1,484)
                                     --------   --------   --------   --------
 Income from continuing
   operations before taxes             29,319     32,753     60,825     72,682
 Provision for income taxes            (9,048)   (10,834)   (17,934)   (24,050)
                                     --------   --------   --------   --------
 Income from continuing operations     20,271     21,919     42,891     48,632
                                     --------   --------   --------   --------
 Discontinued operations
  Discontinued operations (net of tax)   (845)      (963)    (1,487)    (1,312)
  Gain on divestiture (net of tax)      3,437          -      3,437          -
                                     --------   --------   --------   --------
  Total discontinued operations         2,592       (963)     1,950     (1,312)
                                     --------   --------   --------   --------
 Net income                          $ 22,863   $ 20,956   $ 44,841   $ 47,320
                                     ========   ========   ========   ========

 Basic earnings per share
  Continuing operations              $   0.79   $   0.86   $   1.67   $   1.92
  Discontinued operations                0.10      (0.03)      0.08      (0.05)
                                     --------   --------   --------   --------
  Net income                            $0.89      $0.83   $   1.75   $   1.87
                                     ========   ========   ========   ========

  Weighted average common shares       25,699     25,386     25,662     25,336
                                     ========   ========   ========   ========

 Diluted earnings per share
  Continuing operations              $   0.76   $   0.83   $   1.62   $   1.86
  Discontinued operations                0.10      (0.03)      0.07      (0.05)
                                     --------   --------   --------   --------
  Net income                         $   0.86   $   0.80   $   1.69   $   1.81
                                     ========   ========   ========   ========

  Adjusted weighted average shares     26,504     26,341     26,474     26,214
                                     ========   ========   ========   ========


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                     Bio-Rad Laboratories, Inc.
            Summary Condensed Consolidated Balance Sheets

                           (In thousands)
                             (UNAUDITED)





                                                   At June 30,  At December 31,
                                                       2004           2003
                                                   ---------      ---------
 Current assets:
   Cash and cash equivalents                      $  155,329     $  148,642
   Accounts receivable, net                          234,003        234,085
   Inventories, net                                  188,564        190,258
   Prepaid expenses, taxes and other current assets   82,491         97,893
                                                   ---------      ---------
     Total current assets                            660,387        670,878

 Net property, plant and equipment                   186,233        179,123
 Goodwill, net                                        72,741         69,503
 Other assets                                        103,399         67,354
                                                   ---------      ---------
     Total assets                                 $1,022,760     $  986,858
                                                   =========      =========

 Current liabilities:
   Notes payable and current maturities
     of long-term debt                            $    9,987     $   10,423
   Accounts payable                                   67,340         53,995
   Accrued payroll and employee benefits              59,464         71,650
   Sales, income and other taxes payable              12,634         20,833
   Other current liabilities                          61,712         77,425
                                                   ---------      ---------
     Total current liabilities                       211,137        234,326

 Long-term debt, net of current maturities           226,098        225,835
 Deferred tax liabilities                             15,962         13,991
 Other long-term liabilities                          25,043         16,899
 Stockholders' equity                                544,520        495,807
                                                   ---------      ---------
     Total liabilities and stockholders' equity   $1,022,760     $  986,858
                                                   =========      =========


 Certain items have been reclassified to conform to the current
 year presentation.

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                    Bio-Rad Laboratories, Inc.
      Summary Condensed Consolidated Statement of Cash Flows

                          (In thousands)
                            (UNAUDITED)


                                                        Period Ended June 30,
                                                        2004            2003
                                                     ---------       ---------
Cash flows from operating activities:
   Cash received from customers                      $ 517,385       $ 499,425
   Cash paid to suppliers and employees               (440,664)       (409,833)
   Interest paid                                        (9,866)         (9,164)
   Income tax payments                                 (20,860)        (31,632)
   Miscellaneous receipts (payments)                     3,568            (149)
   Discontinued operations                              (2,019)         (2,055)
                                                     ---------       ---------
   Net cash provided by operating activities            47,544          46,592

Cash flows from investing activities:
   Capital expenditures, net                           (29,057)        (25,368)
   Other investing activities                          (16,378)        (14,908)
                                                     ---------       ---------
   Net cash used in investing activities               (45,435)        (40,276)

Cash flows from financing activities:
   Long-term borrowings                                      0          10,835
   Payments on long-term debt                             (212)        (18,109)
   Other financing activities                            3,465           6,002
                                                     ---------       ---------
   Net cash provided by (used in)
     financing activities                                3,253          (1,272)

Effect of exchange rate changes on cash                  1,325          (3,949)
                                                     ---------       ---------
Net increase in cash and cash equivalents                6,687           1,095
Cash and cash equivalents at beginning of period       148,642          27,733
                                                     =========       =========
Cash and cash equivalents at end of period           $ 155,329       $  28,828


Reconciliation of income from continuing operations
to net cash provided by operating activities:

Income from continuing operations                    $  42,891       $  48,632
Adjustments to reconcile net income to net cash
  provided by operating activities:
   Depreciation and amortization                        22,881          20,495
   Changes in working capital                          (19,540)        (37,131)
   Other                                                 2,799          15,908
   Discontinued operations                              (1,487)         (1,312)
                                                     ---------       ---------
Net cash provided by operating activities            $  47,544       $  46,592
                                                     =========       =========


Certain items have been reclassified to conform to
the current year presentation.
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