Abstract: A dehumidifier which vaporizes water separated from gas is disclosed. Relatively hot and humid air is cooled and dehumidified by a refrigerating passageway. Water separated from the hot and humid air is drained into a drainage container via a draining pipe. A plurality of fins extending radially are provided on the outer periphery of a heat radiating portion, which is a portion of a refrigerating circuit. Capillary action of the fins enables the fins to absorb water collected in the drainage container. The water contacts the radiating portion where the water is heated and vaporized.