In recent years, with the continuous adjustment and optimization of energy structure, as well as the ongoing promotion of marine power strategies, there has been increasing attention on the technology of offshore nuclear power generation in China. Due to the complexity of the marine environment where the floating nuclear power station is located, the load borne by the containment shell is far more complicated than that of the onshore nuclear power station. Therefore, it is necessary to study the dynamic performance of the containment shell of the floating nuclear power station through experimental methods to ensure the rationality of the containment design. In this paper, the dimensional analysis is based on the similarity second theorem (π theorem), and the dynamic experiments of containment are designed with the scale ratio of 1:10 and the plate thickness ratio of 1:3. The sensitivity analysis of natural frequency is carried out by the distortion series model of design scale and plate thickness, and the similarity criterion of model frequency distortion is listed to verify the rationality of the design of the dynamic experimental model of containment. This study determines the design method of the dynamic experimental model of the containment of floating nuclear power plant, which has application value for the dynamic model design of various complex spherical structures.