In the present study, the corrosion behaviour of CoCrMo ASTM F75 alloy with boride diffusion layer and undersimulated physiological conditions has been investigated using electrochemical methods. Corrosion has been analyzed usingTafel and electrochemical impedance spectroscopy (EIS) curves. The corrosion resistance optimization of boride diffusionlayer on ASTM F-75 alloy using a central composite design (CCD) in response surface methodology (RSM) has beenstudied. A boronizing thermochemical treatment has been carried out at different temperatures, time periods and paste mass.The roughness for samples subjected to boride annealing has been higher than that of the unboride sample. X-ray diffraction(XRD) measurement has shown that the boride layer of the sample at least consists of a mixture of CoB and CrB phases.The EIS and Tafel curves results have suggested that boride ASTM F75 alloy has not been a suitable candidate fororthopedics applications.