Abstract: In this paper, the authors analyzed water level in earthquakes epicenter region(Dayao, Yongsheng, Ning'er)with M_S≥6.0 strong earthquakes in Yunnan area since 2000. The result shows the common characteristics of water level change in epicenter region before strong earthquakes. Most of strong earthquakes occur during the period of water level going down after gradually going up tiptop. The common characteristics of water level in epicenter region may be helpful to predict place of Yunnan strong earthquakes in the future. The results of statistical analysis show that the high water level in epicenter region before strong earthquakes was caused by rainfall. Since water levels go up or drown, structural stress is accumulated or released, which caused strong earthquakes. This study provides an explanation for the mechanism for earthquake occurrence caused by water motion at earth surface.

Key words: Water level change, Epicenter region, Abnormal characteristics, Yunnan region