Abstract：This paper expatiates the characters in Seismogeologic tectonic and seismicity of Shuikou reservoir, then emphasizes the Gutian ML4.8 seismic sequence and the characteristics of stress field in Fujian area when the earthquake took place on March 6,2008. The preliminary conclusions are as follows. a)The Shuikou reservoir was in a obviously stress accumulation field in March 2008. b)The ML4.8 earthquake was a tectonic earthquake of reservoir, the NE wards Wankou fault may be one of the seismic fault. c) The origin time of the first two M4 events was 12 years, that shows the relation between water’s fluctuation and earthquake was not clear and the change of local tectonic stress was determinant factor leading to earthquake of Shuikou reservoir.
