The main bridge of Wumeng Mountain Bridge on Guizhou Naqing Expressway is a through steel truss concrete composite arch bridge with a calculated span of 270m. On the basis of traditional rigid skeleton arch bridges, the bridge uses steel web members instead of concrete web plates to reduce the structural self weight. The main arch ring adopts a steel truss concrete composite section, and the lifting weight of the segment is reduced by forming the arch ring section in stages. The arch ring of the bridge adopts cable-stayed buckle hanging and cable hoisting, prefabricated and assembled construction, and its segment connection is first connected by steel chord rods embedded in the concrete top and bottom plate of the arch ring, and then connected by pouring segment wet joints. As the first steel truss concrete composite arch bridge, the Wumeng Mountain Bridge has significantly improved the quality control and safety risk reduction of concrete arch bridge construction, and also enriched the construction technology of the steel concrete composite arch bridge, with high innovationg.