Abstract: Control efficacy of different molluscicides on Ampullaria gigas in lotus field were detected in order to effectively reduce the damage of Ampullaria gigas. The results showed that the 40 g 70% Niclosamide wettable power per 667 m² had the most efficient function, the control efficacy was 89.71%, 98.25% respectively when treated for 7 and 15 days, and the efficacy period lasted long, which was 99.5% after treatment for 22 days. The treatment 50 g 70% Niclosamide ethanolamine salt wettable power per 667 m² also had the better control efficacy, which was 81.62%, 94.90%, 95.95% respectively when treated for 7, 15, 22 days. Therefore the 70% Niclosamide wettable power and 70% Niclosamide ethanolamine salt wettable power were recommended to be used alternately to control Ampullaria gigas.