In　this　work　we　prepared　several　CeO2-TiO2　catalysts　for　the　NH3-SCR　reactionusing　co-precipitation　with　assistance　of　microwave　irradiation.　The　catalytic　NH3-SCR　activities　over　CeO2-TiO2　catalysts　at　low　temperatures　are　largely　enhanced　by　the　treatment　of　microwave　irradiation,　the　operation　temperature　window　is　also　broadened.　For　better　understanding　the　promotion　mechanism,　the　catalyst　prepared　by　conventional　co-precipitation　with　and　without　microwave　irradiation　treatment　was　characterized　with　H-2-TPR,　NH3-TPD,　XPS,　XRD　and　BET.　Microwave　irradiation　treatment　accelerates　the　crystallite　rate　of　CeO2-TiO2　catalysts,　and　greatly　enlarges　their　surface　area　by　adjusting　their　microstructures.　The　resistance　to　SO2　and　H2O　is　also　improved　via　regulating　the　hierarchical　pore　structure　by　the　microwave　irradiation.　Microwave　irradiation　treatment　can　also　improve　the　redox　property　and　increase　the　acid　sites　over　the　catalyst　surfaces.　The　result　of　in　situ　DRIFTS　suggests　that　the　microwave　irradiation　treatment　generates　more　Bronsted　acid　sites　on　CeO2-TiO2-2　h　catalyst,　helpful　in　SCR　reactions.　XPS　results　show　that　after　microwave　irradiation　on　the　CeO2-TiO2　catalysts,　the　surface　demonstrates　an　elevated　concentration　of　chemisorbed　oxygen,　consequently　leading　to　better　oxidation　of　NO　to　NO2.　Additionally,　the　molar　ratio　of　Ce3+/Ce4+　has　been　elevated　after　being　treated　by　microwave　irradiation,　a　vital　factor　in　enhancing　the　NH3-SCR　activities.　(C)　2019　Published　by　Elsevier　B.V.　on　behalf　of　Chinese　Society　of　Rare　Earths.