Abstract The molluscicidal activity of Sapindus mukorossi and Terminalia chebula fruit powder against the vector snail Lymnaea acuminata was time and concentration dependent. The molluscicidal activity of T. chebula fruit powder (96 h LC 50:93.59 mg L −1) was more pronounced than that of S. mukorossi fruit powder (96 h LC 50:119.57 mg L −1). Ethanolic extracts of S. mukorossi and T. chebula fruit powder were more toxic than their other organic solvent extracts. The molluscicidal activity of ethanolic extract of S. mukorossi fruit powder (24 h LC 50:2.75 mg L −1) was more effective than the ethanolic extract of T. chebula fruit powder (24 h LC 50:124.06 mg L −1). The 96 h LC 50 of column-purified fraction of S. mukorossi fruit powder was 5.43 mg L −1 whereas those of T. chebula fruit powder was 7.49 mg L −1. Column, thin layer and high performance liquid chromatography analysis demonstrates that the active molluscicidal component in S. mukorossi and T. chebula is saponin (96 h LC 50:1.31 mg L −1) and tannic acid (96 h LC 50:1.64 mg L −1), respectively. These plants may be used as potent source of molluscicides against the snail L. acuminata.