<ARTICLE>                     5
<LEGEND>


                            CASTELLE AND SUBSIDIARIES
                             FINANCIAL DATA SCHEDULE

This  schedule  contains  summary  financial   information  extracted  from  the
Company's Financial Statements for the three month period ending October 1, 1999
included in the  Company's Form 10-Q filed November 12, 1999 and is qualified in
its entirety by reference to such statements.
</LEGEND>
<MULTIPLIER>                                               1,000


                                                        
<PERIOD-TYPE>                                              3-MOS
<FISCAL-YEAR-END>                                    DEC-31-1999
<PERIOD-END>                                         OCT-01-1999
<CASH>                                                     4,453
<SECURITIES>                                                   0
<RECEIVABLES>                                              2,082
<ALLOWANCES>                                               (271)
<INVENTORY>                                                1,545
<CURRENT-ASSETS>                                           8,013
<PP&E>                                                     1,633
<DEPRECIATION>                                           (1,170)
<TOTAL-ASSETS>                                             8,565
<CURRENT-LIABILITIES>                                      4,655
<BONDS>                                                        0
<PREFERRED-MANDATORY>                                          0
<PREFERRED>                                                    0
<COMMON>                                                  28,993
<OTHER-SE>                                              (25,109)
<TOTAL-LIABILITY-AND-EQUITY>                               8,565
<SALES>                                                    4,017
<TOTAL-REVENUES>                                           4,017
<CGS>                                                      1,547
<TOTAL-COSTS>                                              1,547
<OTHER-EXPENSES>                                           3,337
<LOSS-PROVISION>                                               0
<INTEREST-EXPENSE>                                             4
<INCOME-PRETAX>                                            (798)
<INCOME-TAX>                                                   0
<INCOME-CONTINUING>                                        (798)
<DISCONTINUED>                                                 0
<EXTRAORDINARY>                                                0
<CHANGES>                                                      0
<NET-INCOME>                                               (798)
<EPS-BASIC>                                             (0.17)
<EPS-DILUTED>                                             (0.17)