Abstract: Resin cloths, powders, specular bodies and other objects resistant to conventional plating can be plated with metals by a simple method. According to the metal plating method of the present invention, electroless plating is performed after the surface of a object to be plated is treated with a pretreatment agent obtained by reacting or mixing in advance a noble metal compound (catalyst) with a silane-coupling agent having functional groups capable of capturing metals. According to this method, metal plating can be securely applied to powders, resin cloths, semiconductor wafers, and other specular bodies. Moreover, the problem of the insufficient coverage of the seed layer on the inside walls of vias and trenches during the formation of fine wiring can be addressed by applying this method to semiconductor wafers. The silane-coupling agent may be a compound containing azole groups, preferably an imidazole.