A substrate processing apparatus includes a washing liquid supply unit which supplies a washing liquid to a washing liquid discharge port which is open in the outer circumferential surface of a body, a rotation unit which relatively rotates the opposing member and the body around a rotational axis passing through the central portion of the upper surface of the substrate and a washing control unit which controls the washing liquid supply unit and the rotation unit so as to wash the cylindrical gap, where the washing control unit performs a rotation step of controlling the rotation unit so as to relatively rotate the opposing member and the body and a washing liquid discharging step of controlling the washing liquid supply unit so as to discharge a washing liquid from the washing liquid discharge port simultaneously with the rotation step.
