<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
CONDENSED CONSOLIDATED BALANCE SHEET AT OCTOBER 3, 1999 AND THE CONDENSED
CONSOLIDATED STATEMENT OF INCOME FOR THE NINE MONTHS ENDED OCTOBER 3, 1999 AND
IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000097210
<NAME> TERADYNE, INC.
<MULTIPLIER> 1,000
<CURRENCY> U.S. DOLLARS

                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1999
<PERIOD-START>                             JAN-01-1999
<PERIOD-END>                               OCT-03-1999
<EXCHANGE-RATE>                                    1.0
<CASH>                                         121,205
<SECURITIES>                                   102,624
<RECEIVABLES>                                  318,796
<ALLOWANCES>                                     3,843
<INVENTORY>                                    282,631
<CURRENT-ASSETS>                               904,795
<PP&E>                                         945,833
<DEPRECIATION>                                 476,754
<TOTAL-ASSETS>                               1,534,389
<CURRENT-LIABILITIES>                          366,924
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                        21,405
<OTHER-SE>                                   1,119,665
<TOTAL-LIABILITY-AND-EQUITY>                 1,534,389
<SALES>                                      1,242,397
<TOTAL-REVENUES>                             1,242,397
<CGS>                                          738,097
<TOTAL-COSTS>                                1,087,318
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                               1,121
<INCOME-PRETAX>                                166,372
<INCOME-TAX>                                    49,912
<INCOME-CONTINUING>                            116,460
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                   116,460
<EPS-BASIC>                                       0.68
<EPS-DILUTED>                                     0.65