Regarding the issue of roof water inrush caused by disturbance to the overlying rock during coal mining under water bodies, in this paper, the 15102 working face of Zhangshigou coal mine is taken as the research object, and the development height of the water-conducting zone of the 15# coal seam of this working face is obtained by the numerical simulation, segmented plugging and leakage testing and drilling TV method. The simulation analysis and actual measurement results shows that the heights of the water-conducting zone are 49 m and 48.3 m from the simulation and field observation, respectively. The final height of the water-conducting zone is 48.3 m, the fracture-mining ratio is 11.78, and the rock layer type at the upper interface is sandy mudstone, with a thickness of 4.2 m and a distance of about 48 m from the coal seam.