Provided is a dehumidifying kit installed on a drying apparatus that operates an inside drying function when a door is closed and an outside dehumidifying function when the door is open through a suction port and an exhaust port that are provided inside, wherein an opening part of the drying apparatus is partitioned as an opening inlet and an opening outlet, an inner space of the drying apparatus is partitioned as an external air suction flow path from the opening inlet to the suction port and a dry air discharge flow path from the exhaust port to the opening outlet.