Abstract: Aiming at the problems of serious steam cavitation, slow response, high power consumption and poor automation performance for the pumping system in the underground drainage system of a coal mine in Handan, a positive pressure water supply and drainage method is proposed. The submersible pump provides positive pressure water supply for the suction port of the main drainage pump, and the PLC automatic control methods are adopted to optimize and improve the existing system. Combined with the power consumption strategy of “avoiding peaks and filling valleys” and the advantages of frequency control technology for water pump, a safe and reliable automatic control drainage system for the coal mine has been established. After the operation of the system, the electricity cost is reduced, and the start response speed of water pump is increased; the pump units and the auxiliary equipment can be automatically started and stopped according to the height of water level.