To form a moderate solidification layer on the surface of a liquid film while keeping the bulk portion of a coating film in a liquid or half-dried state moderately without using the technique of reduced pressure drying, for a film of processing liquid applied onto a substrate to be treated.

A substrate G coated with resist liquid by an adjacent resist coating unit on the upstream side is transferred onto a roller conveyance route 104 and carried into the housing 112 of a normal pressure drying unit (VD) 46 by flat flow roller conveyance. In the housing 112, the substrate G moving on the roller conveyance route 104 in flat flow is placed in a heating atmosphere HA of high temperature (e.g. 60C) which is higher markedly than that of normal temperature atmosphere. Consequently, thermal energy of the heating atmosphere HA impinges directly on the surface of a resist coating film RM on the substrate G.