To provide a method of electrolyzing molten metal chloride where the turbulence in the flow of a bath within an electrolytic cell is suppressed, the winding-up of impurities stored at the bottom part of the electrolytic cell is prevented, and the reduction of current efficiency is suppressed.

For example, at the time of electrolyzing the molten chloride of magnesium to obtain molten metal, a buffer body 11 is arranged in an electrolytic bath comprising the molten metal chloride held in the electrolytic cell 1, suitably, in the lower part of the section at which the molten metal chloride reaches the electrolytic bath. Further, the injection rate of the molten metal chloride to the electrolytic cell is controlled to ≤100 cm/s.