Abstract: Method and apparatus for processing substrates through a number of wet treatments. A substrate is set on a substrate rotating means for rotation in a horizontal face-up position, within a housing which is open on its top side. By a treating liquid feed means having a treating liquid feed nozzle member, at least one kind of treating liquid is supplied onto upper surfaces of the substrate being rotated by the substrate rotating means. The treating liquid feed nozzle member is supported on a movable arm for displacement to and from an operative position vertically confronting the substrate and a receded standby position away from the substrate on the substrate rotating means. Located face to face with lower surfaces of the substrate is a nozzle means which supplies a fluid to the lower side of the substrate.