In view of the rock mass in the split zone of the TALC SLAB slope of the Liangjiaren Hydropower Station in Jinsha River, Yunnan Province, the impact and collision between the slide mass and the accumulated mass under the slope were considered, and based on the principle of energy conservation, according to the different ways of energy storage in the locked section of the landslide, the speed of the landslide was calculated, and the change of the speed and acceleration in each stage of the landslide was analyzed in turn.Considering the initial sliding velocity and the impact and collision between the initial sliding velocity and the pile body under the slope, it can not be neglected in predicting the speed and scale of the landslide, which can provide a reference for the prediction of other landslide velocities and comprehensive analysis of disaster reduction and prevention after the landslide.