Na has a serious deactivation effect on Mn/TiO2 catalyst for selective catalytic reduction of NO with NH3. In this study, it was found that Sb had a promotion effect on the Na resistance of MnOx/TiO2 catalyst. Then the promotion mechanism was investigated based on the characterization results of BET, XRD, H-2-TPR, NH3-TPD, XPS and in situ DRIFT. The results of H-2-TPR and NH3-TPD showed that the addition of Sb on MnOx/TiO2 could enhance the redox ability and surface acidity respectively, and the results of DRIFT indicated that the addition of Sb on MnOx/TiO2 could generate strong Lewis acid sites on the catalyst surface for NH3 adsorption. Therefore, the doping of Sb has a promotion effect on the Na resistance of Mn/TiO2 catalyst. (C) 2015 Elsevier Ltd. All rights reserved.