The main span of Sutong Bridge is a doublepylon, doubleplane cablestayed bridge with steel box girder, which has the world’s longest central span of 1 088 m within cablestayed bridges. To overcome problems caused by severe meteorological conditions, perplexing hydrological conditions, deep buried bedrock and higher navigation level, many new technics and methods were created. Keys including structural system, steel box girder, stayed cable, tower, pier, tower foundation, collision avoidance system, windresistance, seismicresistance, structural nonlinear response and structural static stability were presented individually in this paper.