The present study focused on the connection between biocompatibility and corrosion resistance for a CoCr alloy. The behavior of a CoCr biomaterial was studied by electrochemical (cyclic voltametry), Fourier transform infra-red spectroscopy (FTIR), surface analysis techniques as scanning electronic microscope (SEM) and X-ray diftractometer (XRD). The surface analysis confirms electrochemical data and the effect of bioactive film on stability.