The invention easily advances following a bent insertion route without specially damaging a function as an angle part. A flexible part is provided between the proximal end part of an end part ring constituting a distal end hard part and the distal end ring of the angle part, wherein the flexible part is composed of a first joint ring body pivoted to the end part ring by a pivot pin and a second joint ring body pivoted to the distal end ring by a pivot pin. The pivot pins are respectively provided on two parts on both left and right side parts, the first joint ring body and the second joint ring body are pivoted by the pivot pins, and when bending force acts on the distal end hard part, the distal end hard part is bent vertically and horizontally at a prescribed angle around the respectivepivot pins.
