To provide an air purifying/ventilating apparatus capable of preventing humidity of purified air supplied into a room from increasing when humidity of fresh air is high.

The present air purifying/ventilating apparatus includes an air purifier 1 which incorporates fresh air and purifying water thereinto and brings the fresh air into contact with the cleaning water, and supplies the purified air into the room. In this case, there are provided fresh air detection means for detecting temperature or humidity of fresh air, indoor detection means for detecting temperature or humidity in the room, and a water supply controller 3 which compares detection results of both of the detection means, and increases the amount of supply of the purifying water to the air purifier 1 when temperature or humidity of the fresh air is lower than those in the room while it decreases the amount of supply of the purifying water or interrupts the supply of the purifying water when the temperature or humidity of the fresh air is higher than those in the room.