For the problems of gas leakage and joint hole operation in the underground drilling of the gas drainage hole in Wangpo Mine, the operation procedure was complicated, without standard, it was not convenient for standardized operation management, and the joint hole was difficult to be reused. The method was optimized and improved, and the effect of the joint hole method before and after the improvement was compared and analyzed. The results showed that the improved new joint hole method greatly improved the air tightness of the system, and was easy to install and disassemble. It had superior field applicability. The gas concentration of the pumping branch pipe adopted the new joint hole method, which effectively improved the extraction and the gas extraction efficiency of the system.