The article clarified, according to the recent research results which have been done in Poyang Lake region of Jiangxi province, bovines are the most important animal hosts of Schistosoma japonicum and infected bovines are main infectious sources of Schistosomiasis in Poyang Lake region. Spring (March to June) is the " cross transmission stage" between definitive host and intermediate host, that is, spring is not only the susceptible season of infection for livestock and human, but also is the susceptible season of infection for snails. In flood season (July to August), the transmission of Schistosomiasis between livestock and snails belong to " low level phase" . Autumn (September to Octber) is the second seasonal peak of cercariae and is the susceptible season of infection for livestock and human. Winter(November to Feburary in next year) is the non- susceptible season of infection. Most of the susceptible zones of infection for livestock, human and snails are the marshlands near the endemic villages.