In view of the problem that the existing ventilation system could not meet the safety requirements after increasing the tunneling face in Huayang No.1 Coal Mine in Shanxi Province, this paper analyzed the current situation of the ventilation system, and analyzed and calculated the required air volume according to the mine connection plan of Huayang No.1 Coal Mine. Based on this, the ventilation system was reformed, and a new return air shaft was built in the southern area. The main ventilators of the mine were reselected and designed, and the FCZ-8-NO.31.5/1800 axial flow fan was selected. The design of the ventilation system transformation scheme had a good practical effect, which ensured the safe and smooth connection of the working face in Huayang No.1 Mine.