An atmospheric pressure plasma generator including: a housing; a first region provided in the housing; a gas heater that causes a heated first processing gas to flow into the first region; a second region provided in the housing adjacent to the first region; a gas cooler that causes a cooled second processing gas to flow into the second region; a plasma generating electrode provided in the second region; a plasma generator that plasmarizes the first processing gas present in the first region using the plasma generating electrode; and an outlet through which plasma gas plasmarized by the plasma generator is ejected.
