Sutong Bridege, whose layout is ( 100 + 100 + 300 ) + 1 088 + ( 300 +100 + 100 ) m, marks the largest span of cable-stayed bridges in the world. The complex natural condition at thr bridge site and the strict requirements for resistance of wind and seismic action make it crucial to choose a favorable structural system to addure the funcrion and safety of the bridge. The comparsion among several optional structural systems for Sutong Bridge is illustrated, the optional structural systems contain floating, viscous damper, hydraulic buffer, and fixed system. After detailed analysis is carried out for viscous damper and hydraulic buffer, super liquid viscous damper with additional displacement limitation is designed for the first application in bridge engineering. The parameters for the damper is analyzed and studied and the dampers are installed sucessfully after required damper tests.