Cu-ZSM-5　(Cu-Zeolite　Socony　Mobil-five)　catalysts　with　different　Cu　loadings　were　prepared　by　ion　exchange　method.　Different　Ce　loadings　were　coated　on　the　surface　of　0.1Cu-ZSM-5　to　form　CeO2-Cu-ZSM-5　catalysts.　Cu　could　improve　the　NH3-SCR　activity　and　broaden　SCR　temperature　window.　0.1Cu-ZSM-5　showed　the　best　catalytic　performance　(above　90%)　in　200-400　degree　celsius.　30%　CeO2-Cu-ZSM-5　catalyst　was　able　to　increase　the　NO　conversion　in　the　low-temperature　region　and　keep　the　activity　unchanged　in　the　high-temperature　region.　CeO2　that　was　coated　on　the　catalysts　preferentially　reacted　with　SO2,　enhancing　the　excellent　anti-sulfur　poisoning　performance.　TPD,　TPR,　and　XPS　results　showed　that　the　synergistic　effect　of　Ce　and　Cu　increased　the　acidic　sites　and　improved　the　redox　capacity　of　catalysts.　According　to　in　situ　DRIFTS　spectra,　Cu-ZSM-5　catalyst　followed　the　Langmuir-Hinshelwood　mechanism,　and　30%　CeO2-0.1Cu-ZSM-5　catalyst　followed　not　only　the　Langmuir-Hinshelwood　mechanism　but　also　the　Eley-Rideal　mechanism.