As oxidation loss can be reduced even if recovered printing plates are directly melted with new metals, a high melting yield equal to that in the case melting is performed with regenerated metals can be obtained. According to the invention, recovered printing plates (35) obtained by recovering used lithographic printing plates (36) and/or edge materials (33) such as cut pieces of the lithographic printing plate and new metals (37) are melted by a burner (19) in a melting furnace (13). The method includes: a first charging step of, at first, charging the recovered printing plates (35) to the melting furnace (13) to form the deposits of the recovered printing plates (35) on the hearth (13B) of the melting furnace (13); and a second charging step of charging the new metals (37) on the deposits of the recovered printing plates (35) to cover the deposits in such a manner that the deposits are not almost exposed, and the flame of the burner is applied to the new metals so as to be melted.