An air filtering apparatus comprising air filtering means (12) for generating electrolytic water containing active oxygen specifies by electrolyzing water, supplying the electrolytic water to a gas-liquid contact member, blowing indoor air to the gas-liquid contact member so as to be brought into contact with the electrolytic water, and blowing out the indoor air to a room, and switching means (30) for switching an operation mode of electrolysis between a first operation mode for electrolyzing pre-electrolysis water so that the concentration of the active oxygen specifies approaches to a target concentration, and a second operation mode for electrolyzing post-electrolysis water so that the concentration of the active oxygen specifies approaches to a target concentration.
