<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
FINANCIAL STATEMENTS OF ALPHA INDUSTRIES, INC. AND SUBSIDIARIES AS OF AND FOR
THE NINE MONTHS ENDED DECEMBER 26, 1999 AND IS QUALIFIED IN ITS ENTIRETY BY
REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>

                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          APR-02-2000
<PERIOD-END>                               DEC-26-1999
<CASH>                                          27,850
<SECURITIES>                                   108,041
<RECEIVABLES>                                   28,403
<ALLOWANCES>                                       712
<INVENTORY>                                      9,324
<CURRENT-ASSETS>                               177,884
<PP&E>                                         128,616
<DEPRECIATION>                                  69,233
<TOTAL-ASSETS>                                 238,828
<CURRENT-LIABILITIES>                           18,786
<BONDS>                                            404
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                         4,944
<OTHER-SE>                                     209,457
<TOTAL-LIABILITY-AND-EQUITY>                   238,828
<SALES>                                        127,837
<TOTAL-REVENUES>                               127,837
<CGS>                                           71,340
<TOTAL-COSTS>                                  106,642
<OTHER-EXPENSES>                                    89
<LOSS-PROVISION>                                   233
<INTEREST-EXPENSE>                             (4,004)
<INCOME-PRETAX>                                 25,110
<INCOME-TAX>                                     9,040
<INCOME-CONTINUING>                             16,070
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    16,070
<EPS-BASIC>                                       0.86
<EPS-DILUTED>                                     0.82