Drainage was an important link in the process of coal mining, which directly affected safety of personnel and equipment. Through the research and design of domestic and international coal mine drainage system, a control system of mine pump based on PLC was proposed, which taking siemens S7-200 as core and equipped with multi sensor monitoring. It could realize online monitoring parameters of water sump level, water pump flux, electric machine and pump temperature etc and had fault alarm and automatic protection function, which not only achieved automatic control of coal mine drainage, but solved problems of high energy consumption and poor reliability of coal mine drainage system to reduce cost.