This this paper, optimization of ultimate bearing capacity of river-to-sea ships structure based on structural analysis using finite element method. The ultimate strength of the hull girder, and calculates the ultimate strength bending moment of the hull girder when B/D=3.0 and B/D=3.5 with the calculation program based on finite element method (B is breadth of the ship, D is depth of the ship). The changing law of ultimate strength bending moment under different transverse frames spacing, ship's depth (D) and member size changes on the load capacity of hull girder are analyzed. The calculations result are provide a reference for the design of the river-to-sea ship structures.