In a substrate processing apparatus, with an internal space of a chamber brought into a reduced pressure atmosphere, a first processing liquid is supplied onto an upper surface of a substrate while the substrate is rotated, and the first processing liquid is thereby quickly spread from a center portion toward a peripheral portion on the upper surface of the substrate. It is thereby possible to coat the upper surface of the substrate with the first processing liquid in a shorter time as compared with under normal pressure. Further, by sucking the first processing liquid from the vicinity of an edge of the substrate, it is possible to coat the upper surface of the substrate with the first processing liquid in a still shorter time. As a result, it is possible to shorten the time required for the processing of the substrate.