The deformation monitoring and safety warning of bridges have always been an important part of mining surveying. Under the influence of coal mining, the ground in the mining area sinks unevenly, causing displacement and deformation of the bridge structure. Bridge deformation mainly manifests in the deformation of the bridge piers, changes in the bridge profile, cracking of the bridge deck, and rotation and distortion of the bridge body. Analogous to buildings such as houses, in bridge monitoring work, the main method is to obtain the displacement of the bridge structure and calculate the bridge movement and deformation; or to use numerical simulation methods to analyze and evaluate the damaged state and deformation mechanism of the bridge from a mechanical perspective, and make damage warnings and propose safety management solutions. However, most of the current analysis examples lack effective combination with actual measurement data, resulting in deviations from reality and making it difficult to provide reference value. Currently, numerical simulation is a commonly used analysis method for analyzing the deformation mechanisms of bridges in mining areas. However, there is a problem with difficult verification through actual measurement analysis. As a result, many deformation and failure warnings for mining area buildings and structures based on numerical simulation deviate from reality and are unable to provide practical reference values. To verify the feasibility of numerical simulation in calculating the deformation of mining area bridges and other buildings and structures, this study takes a reinforced stone arch bridge in a certain mine as an example. Two sets of large-scale surface monitoring data from the mining area are selected to construct surface subsidence contour lines. With this as the boundary conditions, the bridge is numerically simulated to extract the strain results of the bridge’s characteristic points, analyze the displacement and deformation responses of the bridge caused by the subsidence transmission from the ground surface to the bridge. At the same time, the 3D laser scanning results of the bridge for the two monitoring periods are compared to the actual measurements to obtain the displacement and structural deformation results of the bridge during the surface subsidence process. The study shows that, with the actual subsidence of the ground, numerical simulation can calculate the deformation of bridge structure. The effective combination of numerical simulation and field measurement can improve the accuracy of deformation warning for construction, and enhance efficiency in design work.