Abstract: A series of CeO₂-Co₃O₄ supports with variable Ce/Co atomic molar ratio and the corresponding catalysts CuO/CeO₂-Co₃O₄ (CuO loading of 7 wt%) are prepared by co-precipitation and impregnation method respectively, then employed for the preferential oxidation of CO in H₂-rich stream. Techniques such as N₂-sorption, XRD, H₂-TPR were used for catalyst characterization. The catalyst CuO/CeO₂-Co₃O₄ with Ce/(Ce+Co) ratio of 0.9 exhibits the best performance. The addition of a small amount of cobalt to CuO/CeO₂ could enhance the surface area and the dispersion of copper species on the supports. A small amount of cobalt entered the CeO₂ crystal lattice, promoting the interaction between cobalt and ceria, further increases the redox properties of supports and the catalysts.