<ARTICLE> 5 <LEGEND> THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THERMO INSTRUMENT SYSTEMS INC.'S REPORT ON FORM 10-Q FOR THE PERIOD ENDED OCTOBER 3, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS. </LEGEND> <MULTIPLIER> 1,000 <PERIOD-TYPE> 9-MOS <FISCAL-YEAR-END> JAN-02-1999 <PERIOD-END> OCT-03-1998 <CASH> 566,041 <SECURITIES> 6,021 <RECEIVABLES> 396,991 <ALLOWANCES> 25,064 <INVENTORY> 292,342 <CURRENT-ASSETS> 1,331,962 <PP&E> 336,018 <DEPRECIATION> 119,872 <TOTAL-ASSETS> 2,551,649 <CURRENT-LIABILITIES> 576,730 <BONDS> 600,238 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 12,286 <OTHER-SE> 905,818 <TOTAL-LIABILITY-AND-EQUITY> 2,551,649 <SALES> 1,210,345 <TOTAL-REVENUES> 1,210,345 <CGS> 649,118 <TOTAL-COSTS> 649,118 <OTHER-EXPENSES> 107,643 <LOSS-PROVISION> 1,508 <INTEREST-EXPENSE> 34,735 <INCOME-PRETAX> 139,806 <INCOME-TAX> 50,948 <INCOME-CONTINUING> 78,333 <DISCONTINUED> 0 <EXTRAORDINARY> 195 <CHANGES> 0 <NET-INCOME> 78,528 <EPS-PRIMARY> 0.65 <EPS-DILUTED> 0.60