<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 27, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY
REFERENCE TO SUCH FINANCIAL STATEMENTS. THIS SCHEDULE HAS BEEN UPDATED TO
REFLECT THE THREE-FOR-TWO COMMON STOCK SPLIT DISTRIBUTED FEBRUARY 19, 1999.
</LEGEND>

                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          MAR-28-1999
<PERIOD-END>                               DEC-27-1998
<CASH>                                          10,433
<SECURITIES>                                    12,322
<RECEIVABLES>                                   19,961
<ALLOWANCES>                                       643
<INVENTORY>                                      8,883
<CURRENT-ASSETS>                                53,134
<PP&E>                                         104,605
<DEPRECIATION>                                  66,630
<TOTAL-ASSETS>                                  92,367
<CURRENT-LIABILITIES>                           19,551
<BONDS>                                            769
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                         2,655
<OTHER-SE>                                      67,510
<TOTAL-LIABILITY-AND-EQUITY>                    92,367
<SALES>                                         92,070
<TOTAL-REVENUES>                                92,070
<CGS>                                           52,046
<TOTAL-COSTS>                                   78,084
<OTHER-EXPENSES>                                  (15)
<LOSS-PROVISION>                                   170
<INTEREST-EXPENSE>                               (401)
<INCOME-PRETAX>                                 14,402
<INCOME-TAX>                                     1,440
<INCOME-CONTINUING>                             12,962
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    12,962
<EPS-BASIC>                                       0.82
<EPS-DILUTED>                                     0.80