The　Pd-V2O5-WO3/TiO2(Pd-VWT)　catalysts　were　prepared　by　one-step　impregnation　method.　Effects　of　Pd　loading　on　NO　conversion,　sulfur　resistance　and　water　resistance　of　catalysts　had　been　investigated　and　the　optimal　loading　of　Pd　was　0.0075%　with　the　initial　NO　conversion　increased　to　96.2%　at　160　degrees　C　and　finally　slowed　down　to　91.5%　after　1602　hours.　The　NO　conversion　decreased　significantly　in　the　previous　500　hours.　then　maintained　about　90%　with　the　increased　of　tested　time.　NO　conversion　was　more　than　95%　in　the　range　of　159　-380　degrees　C,　and　NO　conversion　was　more　than　90　in　the　range　of　151-400　degrees　C.　Characterizations　of　catalysts　were　carried　out　by　BET,　XRF,　XRD,　FT-IR　and　H-2-TPR.　The　specific　surface　area　of　catalysts　decreased　with　the　loading　of　Pd　increased.　Not　only　the　component　content　but　also　the　crystal　structure　of　catalysts　did　not　change　obviously　after　stability　tested.　The　coexistence　of　SO2　and　H2O　had　a　great　influence　on　NO　conversion　of　catalyst,　and　thermal　regeneration　could　not　completely　recovery　the　activity　of　catalyst,　but　only　prolonged　the　life　of　catalyst.