Abstract: The slope stability of Heidaigou Open-pit Mine in reverse slople mining conditon is taken as the research object, the traditional writing method and similar simulation experiment are used to study roof caving condition and the settlement of slope body and a series of questions for the open pit mine located in the upper goaf under inverse slope mining. The results show that when the heading face is advanced to 40 cm （80 m）, the direct roof is collapsed for the first time, and the initial pressure is 40 cm （80 m）, and the cyclical collapse step is about 25 cm （50 m）; when the excavation is terminated, the collapse angle of the coal wall position is about 56 °, the collapse angle of the open-cut position is about 63 °, the final working face is 280 cm （560 m）. After the excavation is terminated, the maximum horizontal displacement is 1.01 cm （2.02 m）, and the maximum vertical settlement is 4.43 cm （8.86 m）.