Taken a deadweight tonnage 180 000 t bulk carrier as an example, a role played by the bottom end rail of transverse hatch coaming in the structural strength is analyzed, and the possibility of removing this bottom end rail in the bulk carrier is approached. In appropriate cases, after removing the bottom end rail, the ship strength can still be ensured, at the same time, the light weight can be reduced, and the actual hold capacity can be increased, which provides a new train of thought for the ship design optimization.