Abstract: On 24 June 2017, a bedding landslide occurred in Diexi town, Maoxian County, Sichuan, China. The elevation difference of this landslide reached 1 160 m, with a long run-out of 2 200 m. The huge volume of this landslide is relevant to the entertainment during sliding. For researching the effect of entertainment, this paper reveals the process of this landslide based on site investigation, remote sensing image and UAV imagery data: historical earthquakes resulted in broken structures of rock masses; rainfall seeped into the thin layer of slate rock between quartz sandstones through rock failures, simultaneously the pore pressure increased, which results in the source area rock eventually sliding down; then the upper landslide body underwent entrainment at the middle bedrock area, part of which was weathered and lower gravel-soil accumulation area during its run-out process. We simulates the trajectory, velocity and energy of landslide by means of Rocfall software, the results show that centralized entertainment existed in debris flow area and gravel-soil accumulation area, which are exactly the high risk area. The entertainment volumes of the two area are 4.9×106 m3 and 4.38×106 m3, the overall volume of landslide is 13.35×106 m3.The methods of this paper is swiftly and effectively, which can provide reference for disaster relief and calculation of similar landslides.