MEDICAL DEVICE

Provided is a medical device capable of improving handling properties and maintaining excellent insulation properties of conductive wires for supplying electricity to electrodes for performing treatment. A medical device (10) has: an elongated shaft part (20) having a guide wire lumen (27) formed therein, the guide wire lumen being open at a distal part; a plurality of electrodes (40) which are disposed on the distal side of the shaft part (20), extend in the longitudinal direction (X) of the shaft part (20), and are deformable in the radial direction (Y of the shaft part (20) ; and a plurality of conductive wires (50) which extend from the proximal side of the shaft part (20) to the distal side thereof and transfer electricity to an electrode layer (46) . The conductive wires (50) extend inside the electrodes (40) and outside the guide wire lumen (27), and are electrically connected to the electrodes (40) at the distal side of the electrodes (40).