A medical device is configured to prevent a member attached to the distal end of an operation wire passing through a catheter from dropping out from an operation wire. The medical device includes an operation wire which passes through a catheter and which is advanceable and retractable toward the axial direction with respect to the catheter, a distal member interlocked on the distal side of the operation wire, and a grasping unit which is interlocked on the proximal side of the operation wire. The medical device also includes a safety mechanism for releasing the interlock between the operation wire and the grasping unit by a load lower than the breaking strength between the operation wire and the distal member.