A medical instrument, which is capable of holding a wire, includes: a sheath which has a center axis and includes a first contact area capable of being in contact with the wire and a second contact area capable of being in contact with the wire and provided on a proximal end side beyond the first contact area； and a holding portion which is disposed to be advanceable and retractable in a lumen of the sheath and holds the wire. When the wire is disposed to be in contact with the first contact area and the second contact area, the center axis and the wire between the first contact area and the second contact area form an acute angle at a side of the first contact area.
