Abstract: Moving of Oncomelania is the basicway spreading schistosomiasis.It is very necessary for schistosomiasis control to study the motion law of Oncomelania in water.Both the model experunent and the field observation have been used in this study,and a lot of sufficient data have been obtained.Through analysis and research of the data: this paper finds that moving of the overwhelming majorith Oncomelanicas, especially,the longwange moving is achieved with water flow.The moving way of Oncornelania in water have three: as suspended load as bed load and by floating drift.