Abstract: Low temperature selective catalytic reduction of NO by NH3 over V2O5-CeO2/TiO2 was investigated with or without H2O and SO2. Results show that 5V30Ce/TiO2 prepared at 400℃ has high reaction activity, and its NO conversion is 99.2% under the conditions of 10000h-1 and 165℃. When the calcination temperature is below 500℃, Ce does not interact with V and CeO2 is the major existence form at the catalyst surface, which can increase the catalyst surface area and V2O5 dispersion to enhance the catalytic activity. Above 500℃, CeVO4 can be formed and it can decrease the activity. The performance of V2O5-CeO2/TiO2 is superior to resist water poisoning, and the deactivation degree under SO2 is more serious than that under SO2 and H2O.