A medical device includes a medical device body, first and second operating lines inserted in axial direction of the device body, and a bending operating part that pulls the operating lines to perform bending operation of a distal end part of the device body. The device body has the distal end part in the axial direction such that the operating lines are gradually curved and approach each other in circumferential direction of the device body toward a distal end side in the distal end part. The device body has a curved region and a parallel region such that in the curved region, the operating lines gradually curve and approach each other in the circumferential direction toward the distal end side and that in a parallel region, the operating lines extend in parallel to each other between the distal end of the curved region and distal ends of the operating lines.