In this paper, MnOx/TiO2 catalysts with different manganese contents were prepared by using vacuum over-impregnation method to support manganese on TiO2 support. However, the activity temperature window was narrow and the denitrification efficiency was only 265–365 °C in the temperature zone above 80%. Therefore, doping W was used to improve the high temperature activity and broaden the activity temperature window. The experimental results show that the active temperature window of the catalyst is expanded to 260–550 °C when doping 20%WO3. The effects of tungsten doping on the structure and surface properties of the catalysts were investigated by XRD, TEM, Raman, XPS, H2-TPR and NH3-TPD. It is found that the increase of manganese content would increase the ratio of Mn4+ and Oα, and then improve the NH3-SCR activity at low temperature. Tungsten doping can provide more strong acid sites and improve the high temperature activity of the catalyst by inhibiting the oxidation of ammonia.Graphical Abstract: