The Nange Bridge is a reinforced concrete prefabricated cable-stayed bridge. During the process of replacing the stay cables, a temporary cable support system is used to assist in the replacement construction of the stay cables. Due to the special structure of the main bridge, the temporary cables are connected to the main bridge structure using the principle of friction transmission force, and the friction type anchor box is designed. The anchor box system adopts a fully welded structure in the form of a hoop structure. During the replacement of the stay cables, a graded and multiple system transformations are used, Control based on the principle of basic invariance of elevation and displacement