For river-to-sea ship, structural of hatch coaming are expanded to improve transportation, so it affect the longitudinal ultimate strength of the ship hull. Therefore, it is important to conduct the ultimate strength analysis by considering local loads and global loads to ensure the level of safety and reliability of the ship structure.The aim of this paper is focused on the investigation of the structural response and the ultimate strength of the river-to-rea ship using the non-linear finite element method. Analysing strength of the river-to-sea ship hull structure under bending moment, torque and local load. In the structural response analysis, the results shows that maximum stress was occurred on the deck girders due to the sagging bending moment load; minimum stress was occurred on the deck girders due to the hogging bending moment load. For the other three working conditions (hogging bending moment load), the ultimate bending moment value is significantly reduced compared with pure bending.