Abstract: CuO/SC catalysts were prepared by incipient wetness impregnation and characterized by BET, XRD and SEM. Their performance for NO oxidation was tested in a fixed bed reactor. The influence of CuO content, reaction temperature, space velocity, concentration of O₂ and H₂O on NO catalytic oxidation activity were investigated. The results show that CuO/SC with 1% CuO loading had the highest activity at 70 ℃, 5% of O₂ and 1 000 h^-1 of GHSV. In addition, the poisonous effect of water vapor on catalytic oxidation activity was also analyzed. When water vapor was introduced into the feed gas, breakthrough time is reduced from 15 h to 9.5 h.