With the increase of mined-out areas and geological disasters, it is necessary to study the influence range of mining. The 10 mm subsidence boundary is an important indicator to determine the influence range, and FLAC3D is suitable for solving the nonlinear large deformation problem. Therefore, it can be used to explore the relationship between the influence range of surface movement (L) and geological and mining conditions. Taking working faces A and B of two mines, through the establishment of numerical model, the relationship between L and bedrock thickness, loose layer thickness, working face mining length and overlying rock lithology was explored by using control variable method. The calculation formula of L was given and the variation law was analyzed theoretically and mechanically. The results show that L is positively correlated with bedrock thickness and loose layer thickness, while negatively correlated with the mining length. Similarly, L shows a slight increase after the key strata becomes weak. The study provides scientific basis for reasonable coal mining and protection of surface buildings in mining area.