In order to predict the improvement effect of new air shaft in the plan, according to the requirement of safe mining regulation, ventilation resistance was measured before improvement, frictional resistance coefficient of every roadway was calculated, calculating model for mine ventilation system was set up, the ventilation effect of the new air shaft before and after improvement was simulated by Fengwan mining calculation model ventilation system. The result showed that the improvement will perfect the mine ventilation system, reduce ventilation resistance, increase effective air volume, realized zoned ventilation and provide scientific data for the improvement of ventilation system and air volume adjustment.