Abstract: Slope distortion and failure have serious affection not only on security of surface mining,but also on the buildings,equipments and workers standing on the slope.Aiming at the problem on west slope of Bu-zhao-ba Open pit,this research simulates the key section in the slope numerically and obtains the slope stability.The research shows that west slope is unstable and the slope failure will have effect on the normal work.This research result will offer credible gist and technical direction for slope designing and repairing.