Abstract: Disclosed herein is a multi-wire electrical discharge machining system for slicing a workpiece into a thin leaf at intervals of a plurality of wires arranged together causes the plurality of wires arranged together to travel in the same direction and includes a power feed contact configured to collectively comes into contact with the plurality of the traveling wires, a machining power supply portion configured to supply a machining power supply to the power feed contact, and an electrical discharge portion configured to electrically discharge a machining power supply in which the plurality of the traveling wires comes into contact with the power feed contact to collectively supply power to the plurality of the traveling wires to the workpiece, in which a resistance between the machining power supply portion and the power feed contact is smaller than a resistance between the power feed contact and the electrical discharge portion.