The electrochemical behavior of AZ91D and Ti-6Al-4V alloys was investigated in simulated body fluid (SBF) at 37 degrees C. The aim of the present study was to evaluate their corrosion performance through the analysis of corrosion resistance variation with time, using electrochemical impedance spectroscopy (EIS) tests and corrosion current density using potentiodynamic polarization measurements. Very low current density was obtained for Ti-6Al-4V alloy compared to that of AZ91D alloy, indicating a typical passive behavior for Ti alloy. EIS results exhibited high corrosion resistance indicating a highly stable film on titanium alloy compared to magnesium alloy in SBF. Published by Elsevier Ltd.