Metallic materials are widely used in medicine not only for orthopedic implants but also for cardiovascular devices and other purposes. New alloys for biomedical use are developed all over the world continuously to decrease corrosion, toxicity and fracture during implantation and increase interfacial and dynamical tissue compatibility. Most of efforts are made to develop titanium alloys, especially in P-type alloys whose Young's modulus is as low as cortical bone. Nickel-free alloy is also necessary to prevent nickel allergy: nickel-free austenitic stainless steels and shape memory alloys are developed. To increase biocompatibility, the controls of surface morphology and surface treatment or modification are necessary.