Abstract: The Liujiapo landslide is controlled by Hongchunba-Zengjiaba fault. In order to study the formation mechanism of the landslide, based on the field investigation, a three-dimensional finite element numerical simulation model is established. The simulation results with Midas/GTS software show that the fault plays a controlling role of the landslide and the water triggers the occurrence of the landslide. The deformation mode of Liujiapo landslide is summarized as follows. The slope occurs shear failure on the west side where the fault crosses and the frontal zone moves forward to drive the deformation of the east side. As the free face lies in front of the slope, the landslide occurs when a through plane is formed. The results have certain reference function to prevent landslides under similar conditions in the future.