<ARTICLE>                     5
<LEGEND>
THIS  SCHEDULE  CONTAINS  SUMMARY  FINANCIAL   INFORMATION  EXTRACTED  FROM  THE
CONDENSED  CONSOLIDATED  STATEMENTS OF INCOME AND CONSOLIDATED BALANCE SHEETS ON
PAGES 3, 4 AND 5 OF THE  COMPANY'S  FROM 10-Q FOR THE  QUARTERLY  PERIOD  ENDING
NOVEMBER 1, 1997 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL
STATEMENTS.
</LEGEND>
<CIK>                                       0000044764
<NAME>                                    HACH COMPANY
<MULTIPLIER>                                     1,000
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          APR-30-1998
<PERIOD-START>                             MAY-01-1997
<PERIOD-END>                               NOV-01-1997
<CASH>                                           9,485
<SECURITIES>                                       879
<RECEIVABLES>                                   17,666
<ALLOWANCES>                                       265
<INVENTORY>                                     12,899
<CURRENT-ASSETS>                                45,101
<PP&E>                                          75,211
<DEPRECIATION>                                  45,064
<TOTAL-ASSETS>                                  78,786
<CURRENT-LIABILITIES>                           12,665
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                        23,246
<OTHER-SE>                                       8,782
<TOTAL-LIABILITY-AND-EQUITY>                    78,786
<SALES>                                         63,956
<TOTAL-REVENUES>                                63,956
<CGS>                                           32,561
<TOTAL-COSTS>                                   32,561
<OTHER-EXPENSES>                                21,905
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                                 656
<INCOME-PRETAX>                                  9,433
<INCOME-TAX>                                     3,358
<INCOME-CONTINUING>                              6,075
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                     6,075
<EPS-PRIMARY>                                      .32
<EPS-DILUTED>                                      .32