Magnesium metal is an ideal negative electrode material for rechargeable batteries because of its high volumetric capacity and low equilibrium potential. The non-dendritic growth during the deposition process of the magnesium metal is also a significant advantage for the battery applications. In this chapter, we mainly focus on the electrodeposition process of magnesium metal from non-aqueous electrolyte solutions. Firstly, we briefly revisit the overview of the electrolyte design, to understand the electrochemically active species in the electrolyte solutions. Secondly, we discuss some of the details in the deposition/dissolution process of the magnesium metal studied by electrochemical, spectroscopic and theoretical approaches. We also discuss the electrochemical properties, such as overpotential, coulombic efficiency, surface morphologies, crystal growth process, passivation layer and related topics. We also review intermetallic compounds as alternate negative electrode materials.