In a die casting apparatus, during feeding of molten metal by an electromagnetic pump, a molten metal level sensor repeatedly detects a during-feeding level of the molten metal stored in a molten metal holding furnace; a control unit corrects a molten metal feeding voltage to a during-feeding voltage based on the repeatedly detected during-feeding level of the molten metal such that an amount of the molten metal fed by the electromagnetic pump coincides with a prescribed amount; the control unit applies the during-feeding voltage to the electromagnetic pump to cause the electromagnetic pump to feed the molten metal from the molten metal holding furnace into a plunger sleeve; and casting is performed through an injecting operation in which the molten metal fed into the plunger sleeve is extruded by a plunger tip to be injected into a cavity.