Abstract: A drying apparatus for processing a surface of a substrate wherein, when a nitrogen gas is fed to a nozzle, a jet of the nitrogen gas spouted through a jet hole is generated. The jet becomes film-shaped and is projected upwardly along an inner surface of a side wall of a processing vessel. Then, the jet is collected into an outside through a suction port formed in an upper portion of the processing vessel. The inner surface of the side wall of the processing vessel is covered with the jet. Therefore, an IPA vapor can be prevented from condensing uselessly on the inner surface. As a result, the IPA vapor is effectively utilized for condensation on a surface of the object to be processed which is mounted on a pan. Thus, defective dryness of the object can be prevented.