<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  FORM 10-Q FOR THE  QUARTERLY  PERIOD  ENDING
JANUARY 31, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL
STATEMENTS.
</LEGEND>
<CIK>                                       0000044764                     
<NAME>                                    HACH COMPANY
<MULTIPLIER>                                     1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          APR-30-1998
<PERIOD-START>                             MAY-01-1997
<PERIOD-END>                               JAN-31-1998
<CASH>                                           9,757
<SECURITIES>                                       801
<RECEIVABLES>                                   17,255
<ALLOWANCES>                                       274
<INVENTORY>                                     13,765
<CURRENT-ASSETS>                                46,412
<PP&E>                                          76,574
<DEPRECIATION>                                  46,115
<TOTAL-ASSETS>                                  80,866
<CURRENT-LIABILITIES>                           12,702
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                        23,246
<OTHER-SE>                                      10,761
<TOTAL-LIABILITY-AND-EQUITY>                    80,866
<SALES>                                         94,293
<TOTAL-REVENUES>                                94,293
<CGS>                                           48,113
<TOTAL-COSTS>                                   48,113
<OTHER-EXPENSES>                                32,402
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                               1,093
<INCOME-PRETAX>                                 13,471
<INCOME-TAX>                                     4,796
<INCOME-CONTINUING>                              8,675
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                     8,675
<EPS-PRIMARY>                                      .48
<EPS-DILUTED>                                      .48