To provide a gas treatment device capable of effectively decomposing a component which is hardly decomposed by ozone (O).SOLUTION: A gas treatment device has a body, an intake port for introducing a gas to be treated containing oxygen and moisture into the body, a first light source accommodated in the body and having main emission wavelength of 160 nm or more and less than 200 nm, a second light source arranged in subsequent stage from the first light source in view from an intake port side in the body and having main emission wavelength of 220 nm or more and less than 360 nm, a stirring part for stirring a part of the gas to be treated at a position between a terminal of the first light source in the intake port side and a terminal of the second light source in the intake port side, and an exhaust port for exporting the gas to be treated to outside of the body at a subsequent position from the second light source in view from the intake port side.SELECTED DRAWING: Figure 1【課題】オゾン（Ｏ3）によって分解しづらい成分も効率的に分解することが可能な、気体処理装置を提供することを目的とする。【解決手段】気体処理装置は、筐体と、酸素及び水分を含む被処理気体を筐体の内側に導入する吸気口と、筐体に収容され、主たる発光波長が１６０ｎｍ以上２００ｎｍ未満である第一光源と、筐体内において、吸気口側から見て第一光源よりも後段に配置され、主たる発光波長が２２０ｎｍ以上３６０ｎｍ未満である第二光源と、第一光源の吸気口側の端部と、第二光源の前記吸気口側の端部との間の位置において、被処理気体の一部を撹拌する撹拌部と、吸気口側から見て第二光源よりも後段の位置において、被処理気体を筐体の外側に導出する排気口と、を備える。【選択図】 図１
