The present invention provides surface-modified metals such as metal medical devices, e.g., guide wires, syringe needles, and metal tubes in medical devices or equipment, in which a lubricant layer is firmly bonded to the surface to impart lubricity to the surface, and further to improve the durability of the lubricant layer on the surface, thereby reducing deterioration of sliding properties, as well as methods for modifying a metal surface. The present invention relates to a surface-modified metal having a surface at least partially treated by polymerizing a monomer in the presence of a hydrogen abstraction type photopolymerization initiator.