An actuating member for making a flexible elongated member perform a predetermined action includes a push/pull member having a tip side and a base end side, the push/pull member including: a first moving portion and a second moving portion that are located on the base end side of the push/pull member and are movable relative to one another along an axis of the push/pull member, a first extending portion that extends from the first moving portion towards the tip side of the push/pull member, and a second extending portion that extends from the second moving portion towards the tip side of the push/pull member； an operating member that is rotatable about an axis that intersects an axis of the push/pull member, the operating member being configured such that rotation of the operating member causes movement of the first moving portion and the second moving portion.
