Sutong Bridge is a cable stayed bridge with a steel box girder and a main span of 1 088 m. The steel box girder of main-span includes five portions: back span large unit, large block of pylon, standard girder, back span closure girder and middle span closure girder. Each back span large unit was fabricated by welding several deck segments together in factory, and was erected by floating crane. Due to the high of navigational clearance of the main bridge, the traditional truss lifting device couldn't satisfy the requirement of domestic lifting cranes for this kind of lifting height and weight. Hence, a kind of lighter lifting device for the erection of back span large units was accepted for this bridge. In this paper, the design and use of this lifting device is introduced.The upper structure used lifting gantry to install the standard girder segment by cantilever method. Because the bridge's navigation clearance is high, and the girder segment is wide and heavy, the meteorology and hydrology condition of the bridge district is abominable, and the requirements of long cable girder side pull-in, structure and performance propose high request to the lifting gantry. In this paper, key points of designing and using long cable pull-in angle adjustment device integrate into lifting gantry are introduced.