Abstract: In allusion to problems of complicated process, high energy consumption and other issues of traditional manual control mode used in current main drainage system of coal mine underground, the paper proposed using automatic control system of main drainage to achieve automatic control of underground pump, introduced structure, functions and application in Huashan Coal Mine of the system, and introduced device selection and automatic control flow of pump in details. The system takes PLC as control core, uses a variety of sensors to collect parameters of drain and pump motor, and realizes automatic detection and control of operation status and process of pump, which reduces labor intensity of workers and cost of pump operation.