Disclosed is a method of manufacturing an electronic device, comprising forming a concave portion on the surface of a base member, forming an electrically conductive seed layer on that surface of the base member on which a plated film is to be formed, and applying an electrolytic plating treatment with the seed layer used as a common electrode under the condition that a substance for accelerating the electrolytic plating is allowed to be present in the concave portion of the base member in an amount larger than that on the surface of the base member to form a plated film.