Abstract: The coal seam mining is very important to the stability of the landslide when the dip angle of coal measure strata and overying landslide is the same and their inclination is oppsite. Similar material simulation experiment method was adopt to simulate coal mining with coal measures angle of 30°and summarize the instability condition of reverse landslide. The landslide is at critical instability when the caving height of overlying rock is 25.0 m, crack height of overlying strata is 72.0 m and the working face advances 120 m.