Abstract: The green transformation of the shipping industry has put forward a brand new challenge to the drag reduction design of hull structures. In this paper, a 13 000TEU container ship retrofitted with a windbreak structure is taken as the research object. Firstly, the distribution form of windward load is determined through investigation and analysis, and the preliminary structural strength calculation is completed. Subsequently, an optimization scheme for the windbreak wall structure is proposed by integrating the stress response results, and an iterative design is carried out accordingly to achieve lightweight design and meet carbon emission requirements. The results show that structural verification of the windbreak wall should focus on the junction between the bulwark and the bow, and the optimization strategy can prioritize reducing the number of columns, replacing with high-strength steel, and reducing plate thickness. The research results can provide technical references for the modification of this type of ship structure.