To provide an exo-bathroom drying device with a large capacity and a simple structure, using a bathroom heating drier.

The drying device 1 is mainly composed of the bathroom heating drier 3, an adjacently installed ventilation unit 4, and a drying box 2 installed in a dressing room 6. The drying box 2 and the bathroom heating drier 3 are connected by an outgoing side duct S1 and a return side duct R1. The drying box 2 and the ventilation unit 4 are connected by a ventilation duct E1. The drying box 2 is partitioned into two chambers being a drying chamber 2a and a ventilation circulation chamber 2b. A louver 23 is formed in a lower end neighborhood of a partition plate 22. A hot air inlet 24a is provided on a drying chamber 2a top face, and a hot air outlet 24b and a ventilation exhaust port 24c are provided on a top face of the ventilation circulation chamber 2b.