A dryer includes a cabinet, a drum disposed inside the cabinet to accommodate an object to be dried, a first opening disposed on a front side of the cabinet to enable the object to be dried to be placed into the drum, a heat exchanger disposed inside the cabinet to exchange heat with air, a second opening disposed on the front side of the cabinet, and a dehumidification unit. The dehumidification unit is configured to supply outside air to the heat exchanger and air supplied to the heat exchanger is circulated from the heat exchanger into the drum and discharged from the drum to the dehumidification unit. The air discharged from the drum to the dehumidification unit is then discharged outside of the cabinet by the dehumidification unit.