PURPOSE: To prevent the development of defective in a casting product, such as the development of casting blow hole, the mixture of solidified piece by preventing the lowering of temp. and the oxidation of molten metal poured into a cavity as little as possible.

CONSTITUTION: In a molten metal supplying device 5 for casting, in which the molten metal E is poured into the cavity C to cast the casting product, a molten metal supplying device 1 for supplying the molten metal E of aluminum, zinc, etc., melted in a melting furnace R into a pressurized furnace 2 through piping and the pressurized furnace 2 for storing the supplied molten metal E in the condition of heating and holding in the air-sealing atmosphere and forcibly feeding into a sleeve S communicated with the cavity C through a heating introducing tube are provided. Further, the heating introducing tube 3 for introducing the molten metal E in the heating and holding condition and a controller 4 for controlling the heating and the holding of molten metal E, the forcibl feed into the sleeve S and the injection into the cavity C at high pressure are provided.