CO is toxic and detrimental to human beings and the atmosphere. The presence of CO has become one of the important indicators for evaluating ambient air quality. Iron and steel sintering generate large amounts of flue gas emissions containing approximately 1% CO, which has become an important factor restricting the improvement of air quality in steel cities. The catalytic oxidation method is the simplest and most effective method for CO emission control. In this work, a series of CuxCey/TiO2 catalysts with different Ce doping levels were prepared by a one-step impregnation method and subsequently tested for catalytic CO oxidation. The Cu0.5Ce0.5/TiO2 sample has the best catalytic activity under the conditions of 1% CO and 10% H2O. The catalysts were next characterized by XRD, BET, TEM, H-2-TPR, XPS and in-situ DRIFTS methods. The characterization results show that Ce doping promotes the dispersion of copper species on the catalyst surface and improve the redox performance of the catalyst. The results of in-situ experiments showed that both Cu/TiO2 and Cu0.5Ce0.5/TiO2 catalysts followed Mars and van Krevelen mechanism, and Ce doping enhanced the adsorption and activation of oxygen, thus improving the low-temperature reaction activity of the catalysts. [GRAPHICS] .