Provided is a metal film forming apparatus capable of forming a uniform metal film on a surface of a substrate by uniformly pressurizing an electrolyte membrane against the surface of the substrate. The film forming apparatus includes first and second film forming units, a coupling portion that couples the first and second film forming units together, a pressure device including a pressure unit that pressurizes substrates with electrolyte membranes of the respective film forming units via the coupling portion, and a power supply unit adapted to apply a voltage across each anode and each substrate. The film forming units are coupled to the coupling portion via their respective first elastic bodies that elastically deform in the pressurization direction of the pressure unit.