A novel activated carbon-supported vanadium oxide catalyst was studied for SCR of NO with NH3 at low temperatures (100-250 degrees C). The effects of reaction temperature, preparation conditions and SO2 on SCR activity were evaluated. The results show that this catalyst has a high catalytic activity for NO-NH3-O-2 reaction at low temperatures. Preoxidation of the calcined catalyst helps improve catalytic activity. V2O5 loading, other than calcination temperature, gives a significant influence on the activity. SO2 in the flue gas does not de-activate the catalyst but improves it. A stability test of more than 260 h shows that the catalyst is highly active and stable in the presence of SO2.