Abstract: The engineering landslide on Qingzi expressway is taken as the research object. Geologically, the formation of landslide is greatly affected by the underlying soft sandy silt layer, of which the strength decreases greatly when saturated with water. From the engineering conditions, due to the slope toe excavation for construction of service area, the initial stress balance is destroyed to generate a free face conductive to landslide. The above two factors together lead to the occurrence of engineering landslide. The FLAC3D software is used to simulate the occurrence mechanism of landslide after excavation, and the results have verified the accuracy of the analysis. The anti-slide pile will be adopted for the treatment measures. The strengthening effect of anti-slide pile is simulated by FLAC3D, and the results show that the landslide will be steady as a whole after the anti-slide pile treatment.