Abstract: With a growing shortage of mineral resources, the exploitation of deposits under building, road and waters has become of great significance to China's economic development. Above Yunjialing Iron Mine are Yunjialing Village and Yushiwa Iron Mine' living area, and therefore, it belongs to this type of mines. In its mining plan, the method of room-and-pillar mining with subsequent filling is adopted and 21% permanent pillars is reserved as the result of  project analogy method. The simulation work is made with the finite difference FLAC software. A simplified mechanical model is established based on the investigation of mine engineering geology, stope structural parameters and in-situ stress field. The surface deformatin law deduced from the simulation results is: the surface subsidence value is the largest at the center of mined-out area, making the area form a basin, in which the subsidence is roughly symmetrical, with the largest subsidence value corresponding to the center point of the area.

Key words: Subsequent filling, Permanent ore pillar, Surface subsidence