A study to evaluate an antimutagenic potential of water, chloroform and acetone extracts of Triphala has been made in an Ames histidine reversion assay using TA98 and TA100 tester strains of Salmonella typhimurium against the direct-acting mutagens, 4-nitro-o-phenylenediamine (NPD) and sodium azide, and the indirect-acting promutagen, 2-aminofluorene (2AF), in the presence of phenobarbitone-induced rat hepatic S9. A combination drug ‘Triphala’ — a composite mixture of Terminalia bellerica, T. chebula and Emblica officinalis, has been used in traditional system of medicine for the treatment of many malaises, such as heart ailments and hepatic diseases. The drug was sequentially extracted with water, acetone and chloroform at room temperature. The study revealed that water extract was ineffective in reducing the revertants induced by the mutagens. The results with chloroform and acetone extracts showed inhibition of mutagenicity induced by both direct and S9-dependent mutagens. A significant inhibition of 98.7% was observed with acetone extract against the revertants induced by S9-dependent mutagen, 2AF, in co-incubation mode of treatment. Various spectroscopic techniques, namely ¹H-NMR, normal ¹³C-NMR, distortionless enhancement by polarization transfer (DEPT-90 and DEPT-135), UV and IR, are under way to identify the polyphenolic compounds from an acetone extract.