Abstract: In view of the insufficient capacity of the drainage system of the coal seam and goaf in the surface gas pumping station of Pingshang Coal Mine, it is analyzed that the practical problems such as the excess velocity of pipeline and the insufficient negative pressure capacity at the end of the port in drainage system, system transformation and upgrading of high and low pressure systems have been carried out, such as replacing large diameter pipes and installing new pipe wells, etc. The drainage resistance of the mine has been greatly reduced, and the capacity of the drainage system has been greatly improved, under the premise of not updating the high power pumping pump.