To enhance the ride comfort of nonlinear vehicles under non-Gaussian road profile stimulation, the suspension parameters are optimized based on response surface method and multi-objective genetic algorithm in this paper. Firstly, the response characteristics of nonlinear suspension excited by non-Gaussian road profile are analyzed. Secondly, the suspension stiffness and damping are selected, and the response surface model is fitted by least square method. The vertical weighted acceleration, suspension travel and wheel displacement of sprung mass are selected as optimization objectives. Finally, the multi-objective genetic algorithm is used to improve the response surface model in the feasible region of optimization parameters. The results show that although the suspension travel and wheel displacement are almost unchanged, the vertical weighted acceleration is improved by 6%.