Using electrochemical impedance spectroscopy (EIS) and relaxation method with galvanostatic perturbation (RM) the kinetics and mechanism of the magnesium electrode reaction in pure molten MgCl2 have been determined at several temperatures. A three-step electrode process has been found, the high frequency process being pure charge transfer with the low frequency process showing mixed charge transfer-diffusion character. The low frequency step has also been treated as a preceding chemical reaction followed by charge transfer. On the basis of the corresponding exchange current densities and Warburg diffusion impedance, a mechanism of the overall electrode reaction in this melt is proposed.