A series of CuCe catalysts were prepared by an incipient-wetness impregnation method for selective catalytic reduction of NO in combination with dielectric barrier discharge plasma. The effect of the Cu/Ce mass ratio on NO and NOx (NO + NO2) removal efficiency has been studied as a function of energy density at ambient temperature. The catalyst samples were characterised by BET, XRD, XPS, H-2-TPR and NH3-TPD. The results indicated that catalyst addition enhances NO and NOx removal based on only the plasma process. The CuCe catalysts exhibited higher reduction performance compared with the 4 wt.% Cu or 4 wt.% Ce catalysts, and the catalyst with 4 wt.% Cu and 4 wt.% Ce showed the best reduction performance with the highest NO and NOx removal efficiencies of 90.7% and 80.1%, respectively, at an energy density of 367 J/L. The interactions between Cu and Ce increase oxygen migration to form oxygen vacancies, which facilitates the oxidation of NO to NO2, and NO2 favours NO removal via a fast selective catalytic reduction reaction at low temperature. In addition, the CuCe catalysts exhibited low thermal stability, thereby facilitating the catalytic reduction of NO at ambient temperature. (C) 2017 Elsevier B.V. All rights reserved.