Abstract: Taking rock slope formed in the process of excavation in the west as project background，the numerical simulation on the law of stress evolution and deformation on the excavating direction of rock slope was carried out by numerical simulation software- FLAC3D.The results showed that the stress of rock slope formed by excavation was significantly reduced in the process of open excavation，showing like “W” from up to down，and tensile stress zone was formed in the middle of model，which was one of key reasons that caused rock slope failure.Significant expansion deformation of rock slope appeared in the process of excavation，and it was bigger as the increase of depth.The deformation along the direction of excavation at foot of the rock slope was maximum because of the rule of complicated stress evolution.

Key words: Rock slope, Excavation, Stability, Numerical simulation