A nonconductor product is soaked in a solution suspending a semiconducting powder
and is subjected to light irradiation in the solution so that polar group is formed
on the surface of the nonconductor product, and then electroless plating is performed
on the surface on which the polar group is formed. A resin product is subjected
to electroless plating after ultraviolet treatment in which ultraviolet rays are
irradiated through water or a solution is performed. Further, electroless plating
or electroplating with a different or the same kind of metal is performed on the
electroless-plated layer formed by electroless plating. With the method like this,
the plated nonconductor product which does not cause problems such as environmental
pollution and waste liquid treatment, and whose surface and plated coating is firmly
adhered to each other, and, when a resin product is used as an object to be plated,
deformation by heat of the resin product can be prevented, and moreover, the adherent
strength of the plated coating can be improved.