To provide a supporting structure of a rotating section which offers not only facilitated mounting but also resistance to dropout. There are provided a handle base 1 for rotatably supporting one end side of a handle grip 2, and a lever 3 which has a shaft section 23 rotatably supported by a bearing section 11 of the handle base 1 and which is rotated upon pulling of the handle grip 2. The lever 3 includes a first shaft tip section 27 projecting from the shaft section 23 to a shaft tip side and having a part cut away so as to form a circular face, and a second shaft tip section 28 projecting from the first shaft tip section 27 to a shaft tip side and having a width smaller than that of the first shaft tip section 27. The handle base 1 includes a bearing hole 16 for rotatably supporting the first shaft tip section 27 and the second shaft tip section 28 of the lever 3, a first guide rail 17 for guiding the first shaft tip section 27 to the bearing hole 16, and a second guide rail 18 narrower than the first shaft tip section 27 for guiding the second shaft tip section 28 to the bearing hole 16.