A rinsing liquid (DIW) is discharged from a rinsing liquid discharge port formed in a blocking member to perform rinsing processing to a substrate surface while a nitrogen gas is supplied into a clearance space, and a liquid mixture (IPA+DIW) is discharged from a liquid mixture discharge port formed in the blocking member to replace the rinsing liquid adhering to the substrate surface with the liquid mixture while the nitrogen gas is supplied into the clearance space. Thus, an increase of the dissolved oxygen concentration of the liquid mixture can be suppressed upon replacing the rinsing liquid adhering to the substrate surface with the liquid mixture, which makes it possible to securely prevent from forming an oxide film or generating watermarks on the substrate surface.