Abstract: This paper analyzes the slope stability of inner dump covering end-slope after the end-slope mining of a domestic open-pit coal mine by means of theoretical analysis and numerical simulation. Firstly, the theoretical model of inner dump covering end-slope is established from two-dimensional view point. At the same time, the calculation formula of slope safety factor after inner dump covering end-slope is given, and the mechanism of slope safety improvement in this process is expounded. Then the numerical analysis software FLAC3D is used to analyze the stability of the end-slope without inner dump after the end-slope mining, and the process of inner dump covering end-slope is divided into three stages. According to the simulation results, the follow-up of the inner dump obviously reduces the shear strain increment of end-slope rock, and the deformation range and amount of rock also obviously reduce. Therefore, the inner dump can effectively improve the slope safety. Especially, in the early stage of the inner discharge work, the effect of increasing the stability of the end-slope is the best.