Abstract: A casting furnace for continuous casting of magnesium comprises a furnace body divided into at least two compartments by at least one vertical weir. Inside each compartment, an upper layer of molten magnesium is in contact with a lower layer of a liquid heating medium, preferably a molten salt. The top of the weir is situated below a maximum level of the molten magnesium in the furnace. The weir is free of openings between its top and the magnesium/salt interface. The molten magnesium from primary (electrolytic) production or an alloy preparation furnace is introduced into a feed compartment of the furnace through a discharge pipe having means to direct the magnesium horizontally along the magnesium/salt interface, thereby minimizing intermixing of the magnesium and salt layer.