A novel type of Ce-Mo-O-x catalyst prepared by the facile coprecipitation method has been utilized for the selective catalytic reduction of NO with NH3. The catalyst showed excellent activity, prominent resistant to the space velocity in a temperature range from 200 to 400 degrees C and exhibited high SO2/H2O durability at 300 degrees C. XRD and in situ DRIFTS proved that the strong interactions between CeOx and MoOx in the catalyst could be the main reason for the excellent NH3-SCR catalytic performance.