The paper describes the definition of ElNino events and discusses the influence of ElNino events on the summer precipitation over East China under different climatic backgrounds.The analysis suggests that 14El Nino events have occurred since the 1950s and the SST in Equatorial Pacific exhibited a significant increasing trend from the late 1970s to early 1980s.Under different climatic backgrounds ElNino events have different influence on the summer precipitation over East China,but have the same influence-less summer rainfall over the middle and lower reaches of the Changjiang river and the Changjiang-Huaihe valley.