Catalytic system formed by CuO supported on six commercial Ce(x)Z(1-x)O(2) mixed oxides with Cu loading of 7 wt.% has been prepared by conventional wetness impregnation method. These catalysts have been screened for CO oxidation and characterized by means of XRD, BET, Raman and temperature programmed experiments. Activity in CO oxidation has been discussed and correlated with redox properties of catalysts. Below 175 degrees C the catalysts reducibility correlates with ceria content in the support, although an increase of Zr content in the support increases considerably the reduction degree of the ceria-containing supports up to 600 degrees C. Activity in CO oxidation correlates with Ce/Cu molar ratio, which resulted in a linear correlation between preexponential factor and surface Ce/Cu ratio. A compensation effect was found for ceria-containing catalysts. (C) 2010 Elsevier B.V. All rights reserved.