Abstract: Coal fire and coal mine gas explosion generate a large number of CO gas.When the people enter into the refuge chamber,the CO gas penetrates the chamber with the door opened.CO is difficulty to eliminate,which takes a major threat to the life safety of the staff.This paper researches the effect of using the air curtain to prevent the outdoor CO gas into the chamber refuge by numerical simulation,and analyzes the jet velocity,jet angle and the effect of jet angle on the performance of air curtain.The optimization parameters of air curtain have been obtained which maximally ensures safety of miners.