The　Cu-based　transition-metal-oxide　catalysts　were　widely　applied　for　the　selective　catalytic　reduction　of　NOx　with　NH3　(NH3-SCR),　but　limited　in　practical　application　because　of　the　inferior　catalytic　performance　at　high　temperatures.　To　counter　this　issue,　we　designed　a　facile　in　situ　strategy　to　obtain　sulfated　CuCeZr　catalysts,　on　which　the　sulfation　degree　could　be　precisely　controlled　without　any　further　post-treatment.　The　sulfated　CuCeZr　catalysts　not　only　show　broader　SCR　reaction　temperature　window　and　promoted　N-2　selectivity,　but　also　demonstrate　satisfactory　tolerance　to　H2O　and　SO2.　The　outcomes　indicate　that　stronger　surface　acidity,　weaker　reducibility　and　excellent　stability　for　adsorbing　NH3　on　the　sulfated　CuCeZr　catalysts　greatly　suppress　the　undesired　excessive　oxidation　of　NH3　at　high　temperatures,　which　enhance　the　high-temperature　activity　and　N-2　selectivity.　Furthermore,　the　transient　in　situ　DRIFT　and　steady-state　kinetic　studies　reveal　that　both　unsulfated　and　sulfated　catalysts　mainly　follow　the　Eley-Rideal　mechanism.