The　CeO2-V2O5-WO3/TiO2　(CeO2-VWT)　catalysts　were　prepared　by　one-step　and　two-step　impregnation　methods.　The　effects　of　different　loading　of　CeO2　and　different　preparation　methods　on　De-NOx\　activity　of　catalysts　had　been　investigated.　CeO2　helped　to　improve　the　De-NOx　activity　and　sulfur　resistance.　The　optimal　loading　of　CeO2　was　3%　with　the　De-NOx　efficiency　reached　89.9%　at　140(circle)C.　The　results　showed　that　the　De-NOx　activity　of　3%　CeO2-VWTcatalysts　by　one-step　method　was　the　same　as　two-step　method　basically　and　reached　the　level　of　industrial　applications,　the　N-2　selectivity　of　catalysts　was　more　than　99.2%　between　110(circle)C　and　320(circle)C.　In　addition,　CeO2　promoted　the　oxidation　of　NO　to　NO2,　which　adsorbed　on　the　Lewis　acid　site　(V5+-O)　to　form　V5+-NO3　and　inspired　the　fast　SCR　reaction.　Not　only　the　thermal　stability　but　also　the　De-NOx　activity　of　catalysts　decreased　with　excess　CeO2　competed　with　V2O5.　Characterizations　of　catalysts　were　carried　out　by　XRF,　BET,　XRD,　TG　and　FT-IR.　BETshowed　that　the　specific　surface　area　of　catalysts　decreased　with　the　loading　of　CeO2　increased,　the　active　components　content　and　specific　surface　area　of　catalysts　decreased　slightly　after　entering　SO2.　Ammonium　sulfate　species　were　formed　in　poisoned　catalyst　which　had　been　investigated　by　XRF,　BET,　TG　and　FT-IR.　The　largest　loss　rate　of　weight　fraction　was　0.024%C-circle　(1)　C　(1)　at　380(circle)C-390(circle)C,　which　was　in　accordance　with　the　decomposition　temperature　of　NH4HSO4　and　(NH4)(2)SO4.