The influence of protein adsorption on the corrosion behavior of surgical metallic biomaterials is presented in this chapter. The protein structure and the metal ion binding phenomenon are described as the first steps in establishing the degradation mechanisms of biomaterials in body fluids. In addition, the main corrosion mechanisms and the effect of proteins on their thermodynamic and kinetic properties are also considered. Finally, experimental electrochemical techniques used for studying the role of proteins in the degradation mechanisms of implants are analyzed. Future challenges in this field are discussed at the end of the chapter.