Provided is a technique that allows a removal of air bubbles that remain on an ionically resistive element.
A plating apparatus 1000 includes a plating tank 10 configured to accumulate a plating solution Ps and including an ionically resistive element 12 arranged in the plating tank, a substrate holder 30 arranged above the ionically resistive element and configured to hold a dummy substrate Wfx, a rotation mechanism 40 configured to rotate the substrate holder, and an elevating mechanism 50 configured to elevate the substrate holder. At least one projecting portion is disposed on a lower surface of the dummy substrate. The at least one projecting portion 60 projects downward from the lower surface. The substrate holder includes a ring 31 projecting below an outer peripheral edge of the lower surface of the dummy substrate. The projecting portion has a lower surface positioned below a lower surface of the ring. The plating apparatus is configured to cause the rotation mechanism to rotate the substrate holder in a state where the elevating mechanism moves down the substrate holder to allow the projecting portion of the dummy substrate to be positioned above the ionically resistive element and to be immersed in the plating solution of the plating tank.