PURPOSE: To prevent wear of wall face of a crucible and breakage of the crucible and to improve durability of the crucible by charging metal raw material for melting and high melting point metal constituting the crucible into the crucible composing of high melting point metal and executing melting.

CONSTITUTION: The crucible 2 for melting U 3 is constituted with W as high melting point metal. In this metal melting apparatus 1, the W granule 4 is charged into the crucible 2, together with the U 3, and by irradiating the electron beam 5, the U 3 is heated and melted. The charging quantity of the W granule 4 is made to the saturated melting quantity of the W or more into the U 3 at the using temp. of the crucible 2. Therefore, as the W exists saturated melting quantity in the molten U 3 or more, the melting of the W from the wall face of the crucible 2 scarcely occurs. Further, the W granule 4 in the molten metal becomes resistance to convection of the molten metal and the irregular and unexpected convective phenomenon is prevented and temp. inclination in the molten metal is held to constant, and local erosion and breakage of the wall face in the crucible 2 is prevented.