Abstract: A negative pressure automatic drainer based on intrinsically safe DC electric valve is designed. Through the design of the drive circuit, protection circuit and control program of the DC electric valve, the 24 V intrinsic safe DC power supply provided by the monitoring power box is used to directly drive the electric valve, automatically open or close the two-way and three-way ball valves on the water drainer for water collection and drainage operation, and regularly discharge the accumulated water in the production pipeline out of the pipeline. The test results show that the drainer driven by the intrinsic safe DC electric valve can effectively discharge the water in the drainage pipeline under the condition of high negative pressure, and can effectively solve the problems existing in the mechanical negative pressure drainer.