Government subsidized microinsurance program could encourage farmers pork production,but it could suffer from moral hazard.By using a quasi-natural experiment which happened in east China,we use propensity score matching method to estimate farmers vaccine use and production behavior under insurance.The results show that access to insurance significantly increases the hog production,but not significant for the sow production.Vaccine use on hogs increased significantly after the withdrawal of insurance,while it is not significant for sows.It seems that moral hazard is less severe for sow insurance.Even for hogs,the magnitude is not economically significant in the extensive margins.These differences were attributed to the different nature of hog and sow,where the former is product and the latter is asset.