Fe-Beta　and　Cu-SSZ-13　catalysts　were　prepared　by　ion-exchange　method,　and　composite　catalysts　were　prepared　using　different　mixing　methods.　Performance　of　the　catalysts　in　catalyzing　NOx　reduction　and　N2O　decomposition　at　the　same　time　was　investigated.　Fe0.4Cu0.1catalyst,　which　was　composed　of　Fe-Beta　in　the　top　layer　and　Cu-SSZ-13　in　the　bottom　layer　with　mass　ratio　of　4:1,　performed　the　best　in　catalyzing　the　removal　of　NOx　and　N2O　simultaneously　and　broadening　the　reactive　temperature　window.　Effects　of　inlet　gas　composition　on　the　conversion　of　NOx,　N2O,　and　NH3　were　investigated.　Physicochemical　characteristics　of　the　catalysts　were　characterized　by　N2　adsorption-desorption,　XRD,　NH3-TPD,　UV-Vis　DRS　and　H2-TPR　techniques.　The　results　showed　that　Cu-SSZ-13　and　Fe-Beta　had　superior　performance　in　catalyzing　NOx　reduction　and　N2O　decomposition,　respectively.　In　the　tested　temperature　range,　NOx　was　reduced　by　NH3　while　N2O　was　decomposed　over　Fe0.4Cu0.1　when　[NH3]/[NOx]　was　1.　NOx　and　N2O　conversion　reached　93.4%　and　100%,　respectively　at　450℃.　Oxidation　of　NH3　by　O2　at　high　temperatures　(＞350℃)　leads　to　decrease　in　NOx　conversion　with　increasing　temperature.　And　the　formation　of　oxygen　species　from　the　decomposition　of　N2O　at　high　temperatures　(≥350℃)　explains　the　efficient　NOx　reduction　without　O2　in　the　inlet　gas.　The　presence　of　2%H2O　in　the　inlet　gas　hardly　affected　the　reduction　of　NOx　and　oxidation　of　NH3　over　Fe0.4Cu0.1　at　high　temperature　(450℃),　but　did　show　reversible　inhibitory　effects　on　the　conversion　of　N2O.　Abundant　isolated　Cu2+　ions　were　detected　over　Cu-SSZ-13,　providing　sufficient　active　centers　for　the　NH3-SCR　reaction.　Both　isolated　Fe3+　ions　and　FexOy　species,　which　can　catalyze　NO　oxidation　and　N2O　decomposition,　respectively,　were　detected　over　Fe-Beta.　Using　the　top-Fe-bottom-Cu　composite　catalyst,　NO　oxidation　occurs　over　Fe-Beta,　which　consumes　oxygen　species　formed　from　N2O　decomposition　and　thus　promotes　the　conversion　of　N2O　at　low　temperatures　(≤450℃).　However,　the　promotion　effect　of　NO　oxidation　on　NOx　reduction　was　insignificant　since　NOx　conversion　was　rather　high　in　the　temperature　range　for　effective　N2O　decomposition.　©　2024　Chinese　Society　for　Environmental　Sciences.　All　rights　reserved.