A dehumidifying apparatus is provided for a dryer, the dryer including a case; a drum disposed inside the case that receives objects to be dried therein; and a hot air supplying device that supplies hot air into the drum and dry the objects to be dried. The dehumidifying apparatus includes a plurality of dehumidifying devices, and is thereby capable of controlling humidity of exhausted air to a required level of humidity by removing moisture contained in air exhausted from the plurality of dehumidifying devices in multiple steps.