In a manufacturing method for an electrode-membrane-frame assembly in a fuel cell, a first frame member and an electrolyte membrane member are arranged in a first mold for injection molding such that the edge of the electrolyte membrane member is arranged on the first frame member, a second mold is arranged to form a resin flow passage for forming a second frame member which is in contact with the first frame member by interposing the electrolyte membrane member, and a part of the edge of the electrolyte membrane member is pressed and fixed to the first frame member by a presser member mounted on the second mold and a molding resin material is injected into the resin flow passage to form a second frame member.