Abstract：Mainly aiming at the special geological engineering condition of Huashiban high rock bedding slope in Liangjiaren Hydropower Station，investigation on the sliding reason of the slope because of the rainfall condition after the earthquake in 1996 is carried out. The side and bottom sliding surfaces and the slope offside tensile rupture zone can be determined，there are two basic problems should be confirmed：(1) run-through ratio of the slope side and offside；and (2) the determination of rock mass mechanical parameters of the bottom sliding surface. The method to confirm these two basic problems through the back analysis of the sliding process of the slope which has been sliding in the history because of the earthquake and the rainfall，and then to compare the back analysis result from local reconnaissance with the rock experimentation results by the Guiyang Investigation and Design Institute，China Hydropower Engineering Consulting Group Co.，and the empirical values of the similar rock slope engineering in China，finally，the reasonable computing parameters are obtained. After above- mentioned work，the slope stability of the Huashiban rock high slope is analyzed，it is shown that Huashiban rock high slope will fail in abnormal state. So it is necessary to reinforce the slope. The computing results of the reinforcement position show that the reinforcement of the bottom slope can not only improve the local slope stability，but also improve the whole slope stability. Then，three reinforcement schemes based on the above work are designed；and the effects of these three reinforcement schemes on slope stability are analyzed. Finally，an optimum reinforcement scheme，which is economical and reasonable，is presented.
