The　distinct　impact　of　Na　on　the　NH3-SCR　activity　of　Cu-based　Beta　zeolites　was　explored　by　incorporating　Cu　onto　Na　and　H-type　Beta　zeolites　via　ion-exchange　and　impregnation　methods.　The　characterization　results　revealed　that　an　appropriate　amount　of　Na　facilitated　the　exchange　of　Cu　ions　into　the　Beta　zeolites,　leading　to　enhanced　acidity　and　NOx　adsorption　properties.　The　CuNa-Beta　catalysts　obtained　through　ion-exchange,　exhibited　decreased　NH3　oxidation　activity　at　elevated　temperatures　while　demonstrated　enhanced　NO　oxidation　activity　at　lower　temperatures,　resulting　in　the　improved　NOx　conversion.　However,　when　the　Cu　loading　was　conducted　by　the　impregnation　method,　Na　remained　in　the　Cu/Beta　zeolites　caused　the　transformation　of　Cu　to　CuOx,　resulting　in　the　inferior　NH3-SCR　performance.　These　findings　demonstrated　the　significant　influence　of　co-cation　Na　and　preparation　methods　on　Cu　locations　and　NH3-SCR　performance　of　Cu-based　Beta　zeolites.　©　2024　Elsevier　B.V.