Abstract: Taking the south third plate area of Duelping coal mine in Taiyuan Xishan mining area as the study area, FLAC3D software was used to establish numerical model to analyze the evolution of surface subsidence coefficient after repeated mining of 2# and 3# coal seams in this area, and the results of numerical simulation experiments show that: the results of the subsidence prediction coincide well with the original results, and the subsidence coefficient shows a tendency to increase with the increase of the number of repeated mining, and it is 1.1 times as high as the full height of one-time mining in the 2# coal seam, and 1.27 times as high as the full height of one-time mining when continuing to mine the lower 3# coal seam. The subsidence coefficient is 1.1 times higher than the total height of one-time mining, and the subsidence coefficient is 1.27 times higher than the subsidence coefficient of the 2# coal seam when the lower 3# coal seam is continued to be mined. The results of the study provide a basis for the prevention and control of surface subsidence and the protection of features under repeated mining of multiple coal seams, and also provide a basic reference for the study of digital geomorphologic evolution of coal mining subsidence areas.