The invention discloses an adjustable bending sheath tube, which comprises a tube body, a traction
fiber and a
handle. The traction
fiber can slide in the tube body and the
handle, the tube body has a near end and a far end, the near end is connected with the
handle, the handle comprises a
branch which is arranged on one side near the near end of the tube body, a movable part which can transversely move along the
branch is mounted on the
branch, a near end of the traction
fiber is fixed on the movable part, a far end of the traction fiber is fixed on the far end of the tube body, an elastic section is positioned near the far end of the tube body, the bending angle of the elastic section is changed when the movable part moves transversely on the branch, and the movable part is threaded with the branch. Compared with bending sheath tubes in prior art, the bending sheath tube is capable of shortening the effective lengthen of the handle and improving the accuracy of the angle controlling, and the operating process is enabled to be convenient and easy to control.