The invention discloses a construction method of long-span composite beam bridge with steel truss and corrugated steel web. The steel truss and corrugated steel web beam segment is arranged outside the fulcrum lining concrete segment in the bridge. The steel truss and corrugated steel web beam segment can effectively share the shear load of beam segment, prevent buckling instability of corrugatedsteel web and structural damage, meet the design requirements of long-span corrugated steel web beam bridge, and solve the problem of large shear of corrugated steel web of long-span corrugated steelweb bridge lining outer beam segment. Accordingly, the inventors also established corresponding construction methods. The invention is applicable to the design and use of beam bridges with spans of 160m and above, and has certain engineering significance and great economic value.