Disclosed is a catalyst which can convert ammonia contained in exhaust gas from an engine of a vehicle equipped with a Urea-SCR (Urea-Selective Catalytic Reduction) system, to nitrogen, and a method for preparating the same. The catalyst can convert ammonia which is failed to participate in a conversion reaction of NOx to N2 and slipped out of the SCR catalyst, to nitrogen via a SCO (Selective Catalytic Oxidation) reaction, before the ammonia is released to the air.