[Problem] The purpose of the present invention is to provide: a plasma melting method for performing, on a material to be processed such as incineration ash and general waste or industrial waste, a processing in which plasma is generated at a low voltage in the upper part of a furnace and the material to be processed is efficiently subjected to a melt-processing; and a plasma melting furnace used for the plasma melting method.[Solution] This invention is characterized in that: a coke layer is first laid on the furnace bottom of a plasma electric melting furnace in which a metal layer is placed on the furnace bottom and in which a plurality of electrodes can be moved vertically by an electrode raising/lowering device, and some of a material to be processed that is at least one among general waste, industrial waste, and incineration ash is charged onto the coke layer; the lower ends of the electrodes are positioned near the furnace bottom and the passage of current is commenced at a low voltage; the lower ends of the electrodes are raised while the passage of current is stable; the material to be processed is subjected to an additional charge; plasma is generated at the lower part of the electrodes at an operation voltage obtained by raising the voltage to a high voltage from the low voltage applied during the stable passage of current; and the material to be processed is subjected to a melt-processing.