Abstract: Based on the characteristics that the tunnel excavation is near fault fractured zone above great burial depth high pressure karst water, the deformation failure of floor strata is increased and sharply reduces effective impermeable layer thickness and then leads to the water inrush accidents, we analyzed the geological engineering conditions of subinclined shaft in a coal mine first mining area, such as overlying strata spatial occurrence, rock mass structure, mechanical properties. Water damage depth of the roadway floor rock stratum and the ordovician limestone aquifer flowing zone height is calculated and simulated by using thin plate theory and numerical simulation methods. The results show that with the increase of the depth of excavation, the closer the fault floor, the greater the destroy depth of the water guide roadway. It predicted that when the subinclined shaft construction is 400 m, there is water inrush hazard. According to the roadway floor strata failure law and flood forecast results, we propose the corresponding prevention and control measures to ensure the smooth construction of inclined shaft excavation project.