目的　探索反复化疗地区日本血吸虫对吡喹酮的敏感性。方法　从洞庭湖反复化疗区及新流行区现场收集获取感染性钉螺 ,分别逸蚴、分组感染小鼠 ;5周后再分对照组和治疗组 ,治疗组用吡喹酮 (6 0 0 mg/ kg体重 ) 1次灌服 ,治疗后 3周与对照组同时剖杀 ,观察记录各组成虫、肝卵、粪卵数和粪便毛蚴孵化阳性率。结果　反复化疗地区与新流行区吡喹酮治疗组减虫率分别为98.2 4 %、98.71% ;粪卵减少率分别为 99.94 %、99.6 4 % ;肝卵减少率分别为 75 .85 %、73.10 % ;两者差异均无显著性。对照组均有毛蚴孵出 ,而各治疗组鼠粪均无毛蚴孵出。结论　洞庭湖反复化疗地区日本血吸虫对吡喹酮敏感性没有发现降低 ,与新流行区比较差异亦无显著性 Objective To explore the sensitivity of schistosoma japonicum to praziquantel in recurrent chemotherapy area. Methods Infected snails were collected on-site from recurrent chemotherapy and new endemic areas in Dongting Lake. The mice were infected with metacercariae and grouped separately. After 5 weeks, the mice were divided into control group and treatment group. Patients in the treatment group were treated with praziquantel (600 mg / kg body weight) once a day. After 3 weeks of treatment, the rats were sacrificed at the same time as the control group. The numbers of adult eggs, liver eggs, fecal eggs and hatching rate of fecal maggsia were observed and recorded. Results The worm reduction rates were 98.2 4% and 98.71% for praziquantel treatment group and 99.94% and 99.6 4% for praziquantel group and 75.85% and 73.10% respectively for the recurrent and new endemic areas %; No significant difference between the two. Control group were hatched miracidia, and mice in each treatment group were free of miracidia hatch. Conclusion The sensitivity of Schistosoma japonicum to praziquantel in the area of ​​recurrent chemotherapy in Dongting Lake was not decreased, and there was no significant difference with the new endemic area