<p>An apparatus for melting a metal provided with a metal melting furnace (10) for melting a metallic raw material with a flame of an oxygen fuel burner (11) to which oxygen is supplied as a combustion assisting gas; and an oxygen supply source for supplying oxygen as a combustion assisting gas to the oxygen fuel burner (11). The metal melting furnace (10) has a preheating section (13) for preheating the metallic raw material above a melting section (12) to which the oxygen fuel burner (11) is attached and a reduced section (14) located between the melting section (12) and the preheating section (13), the reduced section having an inside diameter smaller than those of the melting section and preheating section. The oxygen supply source is a pressure swing adsorption separator (30) employing an adsorbent which adsorbs preferentially atmospheric nitrogen and supplying a low-purity oxygen having an oxygen content of 65 to 94 % to the oxygen fuel burner (11). <IMAGE></p>
