PURPOSE: To facilitate the pouring of molten metal by a method wherein the small hole of a pouring port, penetrating through a central part in up-and-down direction, is formed while the small hole is expanded sequentially to permit the pouring of total amount of molten metal through an opening at the central part of a bottom wall.

CONSTITUTION: A material to be molten is received in a space, enclosed by a side wall 13, a bottom wall 6 and a bottom lid 15, and when an induction heating coil is energized, inserted material near a cooling water passage from the upper part of a segment 3 to a bottom section is molten and cooled, then, is solidified immediately and becomes skull while the material in the central part of said space, which is apart from the cooling water flow passage, begins to be molten since the central section is provided with weak cooling effect. Upon the initial period of melting, the drops of molten metal, adhered to the peripheral rim of the bottom lid 15, bonds the bottom lid 15 to the bottom wall 6, then, the bottom lid 15 is molten and dropped gradually from the central part thereof by heat conduction in accordance with the progress of melting whereby a small hole is produced and expanded gradually while a pouring port is formed in the opening 16 under a condition that the small hole has arrived at the lower end of the central part. Molten metal passes through the pouring port and drops into a casting mold, located below the pouring port, by gravity. According to this method, the molten metal can be poured easily.