The Mn-Ni/TiO2 catalyst was prepared by co-precipitation method and investigated for the low-temperature selective catalytic reduction (SCR) of NO with NH3.In this work, Mn-Ni/TiO2 catalysts were prepared by different precipitants respectively such as sodium hydroxide, carbamide, ammonia or hydrogen peroxide.To investigate the microstructure and performance of catalysts doping nickel, BET, XRD, XPS, H2-TPR and NH3-TPD were employed.The activity of catalysts prepared by different precipitants were studied with the SCR activity reactor in the temperature range 90℃-350℃.The results showed that Mn-Ni/TiO2 (Ni/Ti molar ratio =0.1) catalyst prepared by carbamide-ammonia-hydrogen peroxide compound precipitant had an extraordinary performance even at the low temperature of 120℃.H2-TPR results showed the peak positions shift to lower temperatures, standing for the reduction potential of MnOx species is increased compared to those of Mr/TiO2 catalysts.The interaction of Ni and Mn atoms is beneficial to an enhancement of the oxygen mobility due to carbamide-ammonia peroxide as precipitant.It is worth noting that the low temperature peak area increased by adding hydrogen peroxide as precipitant.XPS results are in agreement with TPR data results that the absence of the high-temperature peak indicates that the dominant phase in the Mn-Ni/TiO2 catalysts is MnO2.Our NH3-TPD results illustrated that for the Mn/TiO2 and Mn-Ni/TiO2 catalysts which are attributed to NH3 desorbed by weak acid sites and Bronsted acid sites.