<ARTICLE>                     5
<LEGEND>
THIS  SCHEDULE  CONTAINS  SUMMARY  FINANCIAL   INFORMATION   EXTRACTED  FROM  NL
INDUSTRIES INC.'S  CONSOLIDATED  FINANCIAL  STATEMENTS FOR THE NINE MONTHS ENDED
SEPTEMBER  30,  2000,  AND IS  QUALIFIED  IN ITS  ENTIRETY BY  REFERENCE TO SUCH
CONSOLIDATED FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER>                                   1,000

                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                              DEC-31-2000
<PERIOD-START>                                 JAN-01-2000
<PERIOD-END>                                   SEP-30-2000
<CASH>                                           125,064
<SECURITIES>                                           0
<RECEIVABLES>                                    153,041
<ALLOWANCES>                                       1,913
<INVENTORY>                                      148,592
<CURRENT-ASSETS>                                 531,563
<PP&E>                                           721,770
<DEPRECIATION>                                   412,170
<TOTAL-ASSETS>                                 1,061,306
<CURRENT-LIABILITIES>                            250,282
<BONDS>                                          244,105
<PREFERRED-MANDATORY>                                  0
<PREFERRED>                                            0
<COMMON>                                           8,355
<OTHER-SE>                                       294,145
<TOTAL-LIABILITY-AND-EQUITY>                   1,061,306
<SALES>                                          724,444
<TOTAL-REVENUES>                                 787,796
<CGS>                                            482,319
<TOTAL-COSTS>                                    482,319
<OTHER-EXPENSES>                                       0
<LOSS-PROVISION>                                      51
<INTEREST-EXPENSE>                                23,470
<INCOME-PRETAX>                                  177,813
<INCOME-TAX>                                      58,843
<INCOME-CONTINUING>                              117,315
<DISCONTINUED>                                         0
<EXTRAORDINARY>                                        0
<CHANGES>                                              0
<NET-INCOME>                                     117,315
<EPS-BASIC>                                         2.32
<EPS-DILUTED>                                       2.31