A substrate processing apparatus includes a tray, a mask and a rotary stage. The tray includes a substrate support configured to support an outer edge portion of a substrate, a mask support provided on an outer periphery side of the substrate support and projected above the substrate support, and a recess provided between the substrate support and the mask support. The mask covers the recess and the substrate support of the tray. The rotary stage includes an electrostatic adsorption surface and a tray mounting portion provided on an outer periphery side of the electrostatic adsorption surface and below the electrostatic adsorption surface. The outer edge portion of the substrate is projected toward the tray mounting portion side from the electrostatic adsorption surface. The substrate support is spaced below the outer edge portion of the substrate. The mask is spaced above the outer edge portion of the substrate.