The invention provides a reduced-pressure drying device excelling in safety even when a substrate is large, and capable of suppressing generation of vibration and of surely preventing transfer generated in an application liquid applied to the substrate. This reduced-pressure drying device is provided with: a chamber having, in a side wall part, a carrying-in port for carrying in a substrate and a carrying-out port for carrying out the substrate therefrom and used for housing the substrate carried in from the carrying-in port in a nearly horizontal form; gate members for opening and closing the carrying-in port and the carrying-out port; a decompression mechanism for reducing the pressure in the chamber with the carrying-in port and the carrying-out port closed by the gate members; a transport mechanism for generally horizontally transporting the substrate to carry it into the chamber from the carrying-in port and for generally horizontally transporting it to carry out it to the outside from the carrying-out port after a reduced-pressure drying process by the decompression mechanism; and a belt capable of evenly supporting the substrate in the chamber without locally supporting it. |