Abstract: Based on discrete-continuous coupling method and taking the end slope after steep mining of thick coal seam open-pit coal mine as research background, the DEM is used to model and analyze the landslide characteristics, damage process and influence range in the potential instability area of the slope; the FDM grid is established for the small deformation part of the slope bedrock to transfer the internal stress of the slope body and improve the calculation speed. The results show that: the location of the slip surface calculated by the discrete-continuous coupled calculation method and the FDM is similar, and it is a circular-shaped landslide. The landslide process starts with a small amount of damage of the bond between the particles on the slope surface by lateral deformation, and the particles roll down and accumulate at the foot of the slope after the bond is broken; then tension cracks appear at the back edge of the slide body, and the slide surface is gradually clear, and the coal seam at the front edge of the slide body is misshapen, which hinders the further development of the slide under the influence of the reverse tilt structure. The rock mass on the lower side of the slope is damaged first, and then the damage area gradually moves up. After the landslide, there are many tensile cracks in the top 580 m level of the slope, and there is obvious subsidence at 61.37 m from the slope shoulder, about 30 m; the rock strata of the slope are obviously staggered, the lower coal steps and roof are pushed to the face of the air, and the horizontal displacement of the lower reaches 42.39 m.