A plated material containing a base material and a metal plating that covers the base material, the base material containing a main raw material free of any carbon materials, and a carbon material that is present inside the main raw material. A plating pretreatment method including a first step of preparing a base material from a main raw material free of any carbon materials and a carbon material, the base material containing the main raw material and the carbon material that is present inside the main raw material; and a second step of charging the base material into a treatment tank, and immersing the base material in a supercritical fluid or subcritical fluid containing an organometallic complex of palladium in the treatment tank.