Abstract: The main drainage pump is the main electricity consuming equipment in coal mines, in view of the safety performance test of 4 main drainage pumps of HDM420-96×10 type in Dingji Coal Mine, it is found that there are problems of low efficiency and high electricity consumption. performance parameters such as general water pump flow rate, lift, efficiency, shaft power and others are arranged and summarized, and water pump performance curves are drawn to study the factors affecting their energy efficiency. The analysis results show that when the flow rate of a single water pump reaches its maximum, the efficiency of the water pump is the highest and the electricity consumption is the lowest; from the perspective of energy consumption, even in the most efficient state, the electricity consumption still exceeds the specification requirements. It is recommended to conduct a comprehensive overhaul,replace the water pump and electrical machinery that meet the drainage requirements, and thereby reduce energy consumption.