Abstract: This paper takes a coal mine in Shandong Province as the research object, and uses FLAC ^3D numerical simulation technology to deeply analyze the influence of short-distance coal seam downfilling mining technology on the overburden migration law. The simulation results show that the elastic modulus and filling rate have similar effects on overburden migration. With the increase of the elastic modulus (filling rate) of the backfill body, the maximum pressure on the boundary coal pillar on both sides of the working face gradually decreases, and the decreasing range shows a decreasing trend, while the vertical stress on the working face backfill body gradually increases. In terms of vertical displacement, in the process of downward filling mining, the roof of the upper coal seam will bulge slightly during the mining of the upper coal seam, while the mining of the lower coal seam will lead to the expansion of the roof subsidence of the upper coal seam, but generally it will not exceed twice of that during the mining of the upper coal seam. Meanwhile, with the increase of the elastic modulus of the backfill body (filling rate), the roof subsidence during the mining of the upper and lower coal seam will gradually decrease. Considering the influence of elastic modulus of backfill and filling rate on overburden migration, when the elastic modulus of backfill body is 0.6 GPa and filling rate is 90%, the overburden subsidence can be effectively controlled and the filling cost can be effectively reduced.