Exhaust gas processing device

The purpose of the present invention is to provide a novel exhaust gas processing device in which a large volume of exhaust gas to be processed can be handled by a small capacity plasma generation device by preheating gas components, of the exhaust gas to be processed, that decompose under high temperature. An exhaust gas processing device 10 preheats exhaust gas to be processed F by heat from at least either an electric heater 15 or a heat exchanger 17 in the presence of moisture, after which, atmospheric pressure plasma P causes the exhaust gas F to undergo thermal decomposition. The interior of a main device body 11 is a thermal decomposition chamber T. A plasma generation device 14 is of a non-mobile type, and is disposed at a top surface 11a of the main device body 11. A reactor 12 has a cylindrical shape and is disposed inside the main device body 11, and an upper end opening 12i thereof is disposed so as to be oriented towards a plasma emission opening 14f of the plasma generation device 14. A moisture