Abstract: The stability of the surrounding rock in a manganese mine is poor, and the thickness of the ore body is relatively thin. The ore body is buried deeply, with a depth of up to 1 400 m. In order to ensure the stability of the surface, the FLAC^3D finite difference procedural law method is used to simulate the impact of underground mining on the stability of the surface. At the same time, the impact of the excavation and filling of the underground ore body section by section on the stability of the stope and the surface is calculated and analyzed. The simulation calculation results show that the movement of the rock layer is a dynamic process transmitted from bottom to top. The underground ore body can effectively reduce the deformation of the surrounding rock and surface subsidence by using the “ fully-mechanized mining” mining method. The subsidence deformation caused by underground mining on the surface is very small, only 2 cm. At the same time, there is no plastic disturbance zone on the surface, indicating that the surface is in a safe and stable state. The research results provide a theoretical decision-making basis for guiding mining production and construction, as well as surface safety and stability.