Objective To understand the emerging and re?emerging trend of Oncomelania hupensis snails in Wuhu City from 1997 to 2012,so as to provide the evidence for developing schistosomiasis control strategy. Methods A retrospective survey was conducted. The emerging and re? emerging snail areas were investigated in various years,water systems,settings and countries (districts)based on the historical snail survey results. Results The accumulative emerging snail area from 1996 to 2007 was 3 479.42 hm2 ,which was mainly found in marshland areas;while the accumulative re?emerging snail area was 1 648.08 hm2 , which was mainly concentrated on the inland areas. The longest duration from snail re ? emergence to snail elimination was 26 years,and the majority of the duration ranged from 3 to 12 years. Conclusion It seems impossible to avoid snail emergence and re?emergence in Wuhu City,which is closely associated with the natural environment and the implementation of schistosomiasis control measures.