Three series of CeO2/CuO samples were prepared by impregnation method and characterized by XRD, N2adsorption-desorption, temperatureprogrammed reduction(TPR), XPS and TEM techniques. In comparison with the samples prepared with CuO as initial support, the samples with Cu(OH)2as initial support have higher reducibilities and smaller relative TPR peak areas, and also larger specific surface areas at calcination temperatures of 400℃–600℃. As a result, Cu(OH)2is better than CuO as initial support for preferential oxidation of CO in excess H2(CO-PROX). The best catalytic performance was achieved on the sample calcined at 600℃ and with an atomic ratio of Ce/Cu at 40%. XPS analyses indicate that more interface linkages Ce-O-Cu could be formed when it was calcined at 600℃. And the atomic ratio of Ce/Cu at 40%led to a proper reducibility for the sample as illustrated by the TPR measurements. Three series of CeO2 / CuO samples were prepared by impregnation method and characterized by XRD, N2adsorption-desorption, temperatureprogrammed reduction (TPR), XPS and TEM techniques. In comparison with samples prepared with CuO as initial support, the samples with Cu ) 2as initial support have higher reducibilities and smaller relative TPR peak areas, and also larger specific surface areas at calcination temperatures of 400-600 ° C. As a result, Cu (OH) 2is better than CuO as initial support for preferential oxidation of CO in excess H2 (CO-PROX). The best catalytic performance was achieved on the sample calcined at 600 ° C and with an atomic ratio of Ce / Cu at 40%. XPS analyzes indicate that more interface linkages Ce-O-Cu could be formed when it was calcined at 600 ° C. And the atomic ratio of Ce / Cu at 40% led to a proper reducibility for the sample as illustrated by the TPR measurements.