Mn-based　catalysts　have　exhibited　promising　performance　in　low-temperature　selective　catalytic　reduction　of　NOx　with　NH3(NH3-SCR).However,challenges　such　as　H2O-or　SO2-induced　poisoning　to　these　catalysts　still　remain.Herein,we　report　an　efficient　strategy　to　prepare　the　dual　single-atom　Ce-Ti/MnO2　catalyst　via　ball-milling　and　calcination　processes　to　address　these　issues.Ce-Ti/MnO2　showed　better　catalytic　performance　with　a　higher　NO　conversion　and　enhanced　H2O-and　SO2-resistance　at　a　low-temperature　window(100-150　℃)than　the　MnO2,single-atom　Ce/MnO2,and　Ti/MnO2　catalysts.The　in　situ　infrared　Fourier　transform　spectroscopy　analysis　confirmed　there　is　no　competitive　adsorption　between　NOx　and　H2O　over　the　Ce-Ti/MnO2　catalyst.The　calculation　results　showed　that　the　synergistic　interaction　of　the　neighboring　Ce-Ti　dual　atoms　as　sacrificial　sites　weakens　the　ability　of　the　active　Mn　sites　for　binding　SO2　and　H2O　but　enhances　their　binding　to　NH3.The　insight　obtained　in　this　work　deepens　the　understanding　of　catalysis　for　NH3-SCR.The　synthesis　strategy　developed　in　this　work　is　easily　scaled　up　to　commercialization　and　applicable　to　preparing　other　MnO2-based　single-atom　catalysts.