Sutong Bridge tower which is 300.4 m is the highest one in the world. The tower anchor area uses the steelconcrete composite structure, its structure and the stress mechanism are complex, so it must be paid more attention to the structure durable issue. The 300 m height makes the tower quite sensitive to the environmental factors such as wind and temperature. The wind resistance safety of tower in construction stage is especially important. In this paper, the design of composite structure is introduced. The key technologies of tower geometry control and wind resistance in construction stage are analyzed.