Abstract: The air purification system of refuge chamber is an important part of underground emergency, which can provide the good living environment for underground emergency evacuation personnel. In this paper, the similar simulation method is used to establish a CO purification experiment model of refuge chamber. Several sets of comparative experiments are carried out. The change law of CO concentration under different wind speeds, different doses and different volumes are analyzed. The judgment criteria for CO purification detection are proposed. The results show that the purification rate of CO increases first and then decreases with the increase of wind speed and dose, and the average purification rate varies by about 5%. When the space velocity value is around 183　418　h-1, the CO purification reaction rate is the fastest. Moreover, the chamber volume of the experimental model has little effect on the purification capacity.