Research conclusions:This four tracks railway wide－trussed cable－stayed bridge is featured with the large span of the cross beam for four tracks，the large bending moment of the end and middle parts of the span and the large bending movement transmitted to the outside of main truss surface．The research shows application of the trilateral truss without tie or vertical K brace can effectively reduce the span of the small cross beam and the outside bending moment can be born by two web nodals at the each lower chord point． Application of the deck system with horizontal K brace and longitudinal beam on the edge deck can improve the loading on the cross beam and main truss by changing load transfer channel to make main truss only bearing nodal load．Through doing the innovative research on the cross section of the wide truss，main truss style and the deck system with horizontal K brace and longitudinal beam on the edge deck，the difficult technical problem in design of the four tracks railway wild－trussed cable－stayed bridge have been solved successfully．