Objective To observe the toxicity of Pulsatilla chinensis (Bunge) Regel saponins (PRS) against Oncomelania hupensis (0.hupensis).Methods O.hupensis snails were exposed to 40％ and 80％ of 24 h LC50 of PRS for 24 h,and then choline esterase (CHE),alanine aminotransferase (ALT),alkaline phosphatase (ALP),lactate dehydrogenase (LDH) activities in cephalopodium and liver of snails were determined.Niclosamide (NIC) was used as the reference molluscicide.Zebra fish lethality test was evaluated to non-target aquatic species of PRS.Results The molluscicidal activity of PRS (LC50 at 24 h:0.48 mg/L) was similar to that of NIC (LC50 at 24 h:0.16 mg/L).Significant alterations about CHE,ALP,and ALT activities both in the cephalopodium and the liver of snails were observed when O.hupensis was exposed to 40％ and 80％ LC50 of PRS or NIC for 24 h.PRS and NIC could not affect LDH activity in the cephalopodium and the liver.Lower toxicity to fish of PRS was observed up to the highest concentration tested than NIC.Conclusion PRS,as compared with the reference molluscicide NIC,is thought to be used for the control of harmful vector snails safely.