In view of optimization design problem of Carbon Fiber Reinforced Polymer (CFRP) hat-shaped stiffened plate for hull, a structural optimization method based on Response Surface Methodology (RSM) is proposed. The static calculation and eigenvalue buckling analysis of CFRP hat-shaped stiffened plate for hull are conducted to obtain the mass characteristic and mechanical property of stiffened plate structure. The response surface test is conducted with Latin Hypercube Sampling (LHS), the iterative optimization is performed with Multi-Objective Genetic Algorithm (MOGA), and the optimal design scheme meeting the dimensional constraints and stability requirements is obtained. The optimization results show that the panel thickness and hat-shaped beam thickness are sensitive to the influence of buckling load and mass of stiffened plate. The prediction accuracy of response surface model is high, and the proposed optimization design scheme is of good applicability, which can provide reference for the optimization design and engineering application of CFRP hull structure.