PROBLEM TO BE SOLVED: To provide a simple assisting tool for climbing and descending a staircase, which can be easily mounted on a columnar handrail typically often used, and is easily handled.SOLUTION: An assisting tool 50 for climbing and descending a staircase is removably mounted on a columnar handrail 3 supported through a mounting bracket 2 from a hanging wall 1 provided on at least one side of the staircase. The assisting tool includes: a frame 51 linearly movable in the longitudinal direction of the handrail 3 and mounted on the handrail 3 a handle 52 provided on the frame 51 and held by a person climbing and descending the staircase and a locking arm (slip preventing means) 53 for preventing the frame 51 from slipping in the circumferential direction of the handrail 3 when the handle 52 is set at a use position.
