An infant incubator including: an infant chamber isolated from external air a conditioning bath communicating with the infant chamber an air-conditioning equipment circulating air in the infant chamber through the conditioning bath a fan provided at the air-conditioning equipment and moving air in the conditioning bath a heater provided at the air-conditioning equipment and heating the air in the conditioning bath a humidifier provided at the air-conditioning equipment, removably installed on a constructional member of the conditioning bath, and supplying water-vapor to the air in the conditioning bath and a channel member for supplying water-vapor removably installed on a water-vapor introduction port penetrating the constructional member of the conditioning bath, and connecting the humidifier and the conditioning bath, in this infant incubator, the channel member for supplying water-vapor closes the water-vapor introduction port when the humidifier is removed, and opens the water-vapor introduction port when the humidifier is installed.