Preliminary field evaluation of 43 rice anther culture lines in 1990 for resistance to the rice water weevil,Lissorhoptrus oryzophilusKuschel, identified several lines with potential for tolerance. The seven most promising lines (952836, 953508, 953509, 953510, 953511, 953527, and 953541) were evaluated for tolerance in 1991 and 1992. The parameters used to assess tolerance included rice water weevil larval population, root pruning damage, plant height, and grain yield. Significant differences were found among the lines tested with regard to rice water weevil larval populations, root damage ratings, plant height, and grain yields. The comparison of insecticide treated and untreated plots indicated that lines 952836 and 953527 exhibited moderate levels of tolerance to the rice water weevil. Tolerance in the lines was expressed, in part, as the ability to recover from root pruning damage and to produce high grain yields.