<ARTICLE>                     5
<LEGEND>
THIS  SCHEDULE  CONTAINS  SUMMARY  FINANCIAL   INFORMATION   EXTRACTED  FROM  NL
INDUSTRIES INC.'S CONSOLIDATED  FINANCIAL  STATEMENTS FOR THE THREE MONTHS ENDED
MARCH  31,  2000,  AND IS  QUALIFIED  IN  ITS  ENTIRETY  BY  REFERENCE  TO  SUCH
CONSOLIDATED FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                   3-MOS
<FISCAL-YEAR-END>                              DEC-31-2000
<PERIOD-START>                                 JAN-01-2000
<PERIOD-END>                                   MAR-31-2000
<CASH>                                             133,698
<SECURITIES>                                             0
<RECEIVABLES>                                      138,959
<ALLOWANCES>                                         2,231
<INVENTORY>                                        173,926
<CURRENT-ASSETS>                                   491,082
<PP&E>                                             759,822
<DEPRECIATION>                                     427,563
<TOTAL-ASSETS>                                   1,029,275
<CURRENT-LIABILITIES>                              260,312
<BONDS>                                            244,207
<PREFERRED-MANDATORY>                                    0
<PREFERRED>                                              0
<COMMON>                                             8,355
<OTHER-SE>                                         253,598
<TOTAL-LIABILITY-AND-EQUITY>                     1,029,275
<SALES>                                            231,009
<TOTAL-REVENUES>                                   235,509
<CGS>                                              159,265
<TOTAL-COSTS>                                      159,265
<OTHER-EXPENSES>                                         0
<LOSS-PROVISION>                                       612
<INTEREST-EXPENSE>                                   7,856
<INCOME-PRETAX>                                     34,998
<INCOME-TAX>                                        11,199
<INCOME-CONTINUING>                                 23,708
<DISCONTINUED>                                           0
<EXTRAORDINARY>                                          0
<CHANGES>                                                0
<NET-INCOME>                                        23,708
<EPS-BASIC>                                           0.47
<EPS-DILUTED>                                         0.46