An actuating member for making a flexible elongate member for medical use perform a predetermined action includes a push/pull member, an operating member, and an advancing member. The push/pull member includes a first moving portion and a second moving portion, which are movable relative to each other. The push/pull member is pushed/pulled in conjunction with a movement of the first moving portion and the second moving portion. The operating member effects the movement of the first moving portion and the second moving portion. The advancing member includes a narrowed portion that moves the first moving portion and the second moving portion in conjunction with an operation of the operating member. The push/pull member makes the elongate member perform at least one of (i) an advance/retraction action and (ii) a bending action by transmitting the movement of the first moving portion and the second moving portion to the elongate member.
