An air conditioner having an interior casing in which an air filter is provided along an inner face of an air suction inlet, includes a filter cleaning part, a cleaning time drive member for moving the air filter and the filter cleaning part with respect to each other, and an ultraviolet light irradiation unit which irradiates the air filter with ultraviolet rays. The air filter and the filter cleaning part are relatively moved by the cleaning time drive member to remove dust adhered to the air filter, and the ultraviolet light irradiation unit irradiates an uncleaned face of the air filter with the ultraviolet rays.