Lenggu hydropower station is located in alpine valley region of Yalong River. Due to the complex geological environment, the stability problem is sever and it is influenced by numerous factors. With slope safety factor chosen to be the index, the unit weight, cohesion, internal friction angle, water level and seismic coefficient were selected to be the factors. Then, the numerical experiments based on uniform design were done and the results were analyzed with grey correlation theory. The result show that the sequence of magnitude of correlation with slope stability is:internal friction angle > water level > seismic coefficient > cohesion > unit weight.