Abstract: An ultrasonic humidifier includes a spraying chamber for receiving water received therein, a vibrator adapted to make ultrasonic vibrations, a blower, and a perfume case. Ultrasonic waves are applied to the water by the vibrator to produce a water spray in the form of a mist. The water spray is emitted, by driving the blower, into a room by way of a jet of air scented by the perfume to thereby not only moisten the air in the room but also to give forth a pleasing fragrance. The humidifier further comprises an air-feeding suction port hole formed in one side wall of a body of the humidifier. The perfume case is installed at the air suction port hole so as to be demountable from outside the body of the humidifier.