Abstract: It is an essential task to explore geological structures in detail in order to degas evenly in coal seams and prevent gas hazards in coal mines. The necessity of the meticulous gas geological exploration in coal mines has been shown through practical examples of gas hazards in China. Main task and requirement of the meticulous gas geological exploration project are put forward for comprehensive utilization of degas boreholes. The design patterns have been expounded upon exploring and dealing with concealed faults in front of tunneling face and in coal mining panel. Feasibility of the design patterns introduced in the paper has been tested and verified in coal mining practice. It is concluded that comprehensive utilization of degas boreholes for locating successionally roof or floor of coal seam could improve exploration accuracy of concealed geological structures, and that is a practical, economic and effective technical way to carry on meticulous gas geological exploration and to prevent gas hazards in coal mines in China.