The Ce modified In/W-ZrO2 catalysts were prepared by impregnation and mechanical mix method. Their activities for SCR of NOx with methane were investigated. The activity of the In/W-ZrO2 catalyst was enhanced by addition of Ce with both methods, while the promotional effect was more pronounced for catalyst prepared by mechanical mix method compared to impregnation method. The function of Ce was to improve the oxidation of NO to NO2. The maximum NOx conversion over the mechanical mixed catalyst can be stabilized at 74% at 450 degrees C in a dry gas flow and 37% at 500 degrees C in wet flow (24,000 h(-1)). For the impregnated catalysts, Ce was found to compete with In to adsorb on strong acid site over W - ZrO2 support and inhibited the formation of InO+, which resulted in the lower activity of these catalysts than mechanical mixed catalysts.