Abstract: Pingzishan landslide is located in Xincun town of Ningnan County in Sichuan Province.The landslide began to slide in 2011,with small deformation every year.The existence of landslide threats the safety of the villagers.Based on the survey on site,the geological conditions,deformation and failure characteristics,evolution process and failure mechanism of the landslide are preliminarily analyzed.At the same time,the stability of the landslide is simulated by FLAC^3D software using the strength reduction method.The results show that:the main deformation zone of the landslide in the rear.The landslide has not yet formed through surface at this moment.However,pay attention to the through surface and the instability of the landslide triggered by heavy rainfall and earthquake.