Objectives To understand the epidemiological characteristics of Japanese Encephalitis in Shanghai and to provide evidence for preventing JE.Methods Epidemic characteristics,JEV antibody in healthy population and swine infection rate in Shanghai were analyzed by methods of field survey,serology and molecular biology.Results JE incident rate in Shanghai was 0.077/100,000 in 2006;and 0.129/100,000 in 2007.Antibody positive rate before JE epidemic fastigium was 60.39%;postive rate after epidemic was 85.44%.JE IgG positive rate was 26.92% in 3-month swine and 14.86% in swine for sale;JE Gene in mosquito was analyzed for type 1.Conclusion The JE prevalence rate is relatively low in Shanghai.JE antibody positive rate is high in Shanghai population.Swine as a media is infected by JE virus.The JE virus in mosquitoes belongs to genotype 1.