The activity of the CuO–CeO2 couple supported on a MSU silica doped with zirconium (Si/Zr = 7), was evaluated in the preferential oxidation of CO (CO-PROX) in hydrogen-rich gas stream (1.2% CO, 1.2% O2, 50% H2, 0–15% CO2, 0–10% H2O He balance) and the catalytic performance was compared with that of CuO–CeO2 supported on a pure MSU silica. The samples were characterized by X-ray powder diffraction (XRPD), N2 physisorption at 77 K, temperature-programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS). Correlations between catalytic performances and physico– chemical properties of the materials have been made.