<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM (a)
THE UNAUDITED, CONSOLIDATED FINANCIAL STATEMENTS OF GENZYME CORPORATION
AND SUBSIDIARIES FOR THE NINE MONTHS ENDED SEPTEMBER 30, 2000 AND IS
QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH (b) FINANCIAL STATEMENTS
AS INCLUDED IN THE FORM 10-Q FOR GENZYME CORPORATION DATED SEPTEMBER 30, 2000.

<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-2000
<PERIOD-START>                             JAN-01-2000
<PERIOD-END>                               SEP-30-2000
<CASH>                                         215,568
<SECURITIES>                                   592,732
<RECEIVABLES>                                  207,079
<ALLOWANCES>                                    23,300
<INVENTORY>                                    123,878
<CURRENT-ASSETS>                               758,762
<PP&E>                                         614,463
<DEPRECIATION>                                 213,833
<TOTAL-ASSETS>                               2,076,546
<CURRENT-LIABILITIES>                          175,549
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                         1,459
<OTHER-SE>                                   1,597,618
<TOTAL-LIABILITY-AND-EQUITY>                 2,076,546
<SALES>                                        654,785
<TOTAL-REVENUES>                               659,402
<CGS>                                          165,631
<TOTAL-COSTS>                                  201,517
<OTHER-EXPENSES>                               272,694
<LOSS-PROVISION>                                 5,574
<INTEREST-EXPENSE>                              12,785
<INCOME-PRETAX>                                166,832
<INCOME-TAX>                                    51,101
<INCOME-CONTINUING>                            115,731
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                   115,731
<EPS-BASIC>                                       2.14
<EPS-DILUTED>                                     1.99

<F1>GENZYME CORPORATION REPORTS EARNINGS PER SHARE FOR EACH OF ITS FOUR SERIES
OF COMMON STOCK. THE EARNINGS PER SHARE INFORMATION PRESENTED ON THIS
SCHEDULE REPRESENTS THE EARNINGS PER SHARE DATA FOR NET INCOME ALLOCATED
TO GENZYME GENERAL STOCK. FOR THE PERIOD PRESENTED, NET INCOME ALLOCATED
TO GENZYME GENERAL STOCK WAS $182,121. FOR THE PERIOD PRESENTED, NET LOSS
ALLOCATED TO MOLECULAR ONCOLOGY STOCK WAS $(17,924) OR $(1.28) PER BASIC
AND DILUTED SHARE OF MOLECULAR ONCOLOGY STOCK, NET LOSS ALLOCATED TO
SURGICAL PRODUCTS STOCK WAS $(34,346) OR $(2.30) PER BASIC AND DILUTED
SHARE OF SURGICAL PRODUCTS STOCK, AND NET LOSS ALLOCATED TO TISSUE REPAIR
STOCK WAS $(14,590) OR $(0.51) PER BASIC AND DILUTED SHARE OF TISSUE
REPAIR STOCK.