The invention relates to a retractable elbow, and belongs to the technical field of cable protection device structures. The retractable elbow comprises an arc elbow pipe. The two ends of the arc elbow pipe are respectively provided with a first socket and a second socket which are integrated with the arc elbow pipe. The horizontal tangent direction of the first socket and the vertical tangent direction of the second socket form an included angle of 90 degrees. A strip opening is arranged along the radian direction of the wall of the arc elbow pipe. The two ends of the opening respectively extend to the ports of the first socket and the second socket. A plugging device for sealing the opening is arranged at the opening. The retractable elbow is reasonable in structure design and easy to install, and can improve the service life of cables, reduce the labor intensity of workers, and improve work efficiency.