A process for producing a metal film, comprising the steps of: (a) forming an organic film by (i) applying a primer composition to a substrate or a film and thereafter (ii) polymerizing the primer composition, the primer composition containing (α) an addition polymerizable compound including three or more reactive groups, (β) an addition polymerizable compound including an acid group, and (γ) an addition polymerizable compound including a hydrophilic functional group; (b) forming a metal salt from the acid group by processing the organic film with an aqueous solution containing a metal ion; (c) substituting the metal salt of the acid group with a metal salt by processing the organic film, which has been processed with the aqueous solution containing the metal ion, with a metal ion aqueous solution containing a metal ion which has a less ionization tendency than the metal ion; (d) reducing the metal ion so that a metal film is formed on a surface of the organic; and (e) oxidizing the metal film, wherein the addition polymerizable compound including three or more reactive groups (α) has a structure represented by the following formula: (R1-R2)n-R3... where: n represents three or more; R1 represents an addition polymerizable reactive group selected from a group consisting of an acryloyl group, a methacryloyl group, an acrylamide group, a vinyl group, and an allyl group; R2 represents an arbitrary structure including an ester group, an alkyl group, an amide group, an ethylene oxide group, and a propylene oxide group; and R3 represents C, an alkyl group, or C-OH, wherein the addition polymerizable compound including an acid group (β) includes, as the acid group, one or more functional groups selected from a group consisting of a carboxyl group, a sulfonate group, a phenolic group, a benzoic acid group, a phthalic acid group, a salicylic acid group, an acetylsalicylic acid group, and a benzenesulfonic acid group, at least one of the one or more functional groups being located at a molecular end, wherein the addition polymerizable compound including a hydrophilic functional group (γ) is a compound represented by the following formula: R1-R2-R1... where: R1 represents an addition polymerizable reactive group selected from a group consisting of an acryloyl group, a methacryloyl group, an acrylamide group, a vinyl group, and an allyl group; and R2 represents a hydrophilic functional group selected from a group consisting of an ethylene oxide group, a propylene oxide group, an acetal group, a hydroxyl group, and an ether group, and wherein the step (e) oxidizing the metal film comprises irradiating the metal film with an ultraviolet ray, plasma or an infrared light, or heating the metal film. (a) forming an organic film by (i) applying a primer composition to a substrate or a film and thereafter (ii) polymerizing the primer composition, the primer composition containing (α) an addition polymerizable compound including three or more reactive groups, (β) an addition polymerizable compound including an acid group, and (γ) an addition polymerizable compound including a hydrophilic functional group; (b) forming a metal salt from the acid group by processing the organic film with an aqueous solution containing a metal ion; (c) substituting the metal salt of the acid group with a metal salt by processing the organic film, which has been processed with the aqueous solution containing the metal ion, with a metal ion aqueous solution containing a metal ion which has a less ionization tendency than the metal ion; (d) reducing the metal ion so that a metal film is formed on a surface of the organic; and (e) oxidizing the metal film, n represents three or more; R1 represents an addition polymerizable reactive group selected from a group consisting of an acryloyl group, a methacryloyl group, an acrylamide group, a vinyl group, and an allyl group; R2 represents an arbitrary structure including an ester group, an alkyl group, an amide group, an ethylene oxide group, and a propylene oxide group; and R3 represents C, an alkyl group, or C-OH, R1 represents an addition polymerizable reactive group selected from a group consisting of an acryloyl group, a methacryloyl group, an acrylamide group, a vinyl group, and an allyl group; and R2 represents a hydrophilic functional group selected from a group consisting of an ethylene oxide group, a propylene oxide group, an acetal group, a hydroxyl group, and an ether group, and