Abstract: Abstract：Objectives Floating raft vibration isolation system is widely used in the vibration isolation and impact protection of ship equipment. The demands for improving the comprehensive performance and lightweight of the floating raft vibration isolation system are increasing in engineering. Methods For this issue, the vibration isolation system of plate-frame floating raft is taken as the research object. Establishment of Finite Element Model Based on Ansys APDL. Calculate the vibration isolation performance and impact resistance. Vibration isolation performance of floating raft is tested through experiments. Verify the accuracy of numerical simulation by comparing with numerical simulation results. Full finite difference method is used to analyze the parameter sensitivity of the floating raft vibration isolation system. Appropriate design variables are se-lected through the sensitivity analysis results. The design of the floating raft isolation system is lightweight based on the RBF-PSO multi-objective optimization algorithm. ResultsThe results show that after optimization, the optimized raft mass is 63.03Kg. Compared with the original raft, the weight of the lightweight raft is reduced by 31.92%. The vibration isolation per-formance of the floating raft isolation system is increased by 2.48 dB. The impact resistance of the equipment is also improved. The error between the optimized value of RBF-PSO and the calculated value of numerical simulation is less than 1%. Con-clusions Therefore, RBF-PSO optimization algorithm can be effectively applied to the lightweight design of the floating raft vibration isolation system.