采用基于超单元的方法对轿车的白车身进行了建模和动态仿真设计 .该方法不仅可以提高计算速度 ,同时可以对轿车车身中的各个子结构进行独立的动态优化设计 .针对轿车设计中平顺性问题 ,还提出了车底板上 2点垂直方向位移响应的均方值为最小的车身优化方法 ,对车身结构进行动态优化设计 ,获得了令人满意的优化结果 . This paper uses the method based on superelement to simulate and design the white body of the car, which not only can improve the calculation speed, but also can independently and dynamically optimize the sub-structures in the car body.Aiming at the smooth design of the car, In addition, a vehicle body optimization method is proposed to minimize the mean square value of the displacement response at 2 o’clock on the vehicle floor, and the optimization of the vehicle body structure is achieved with satisfactory optimization results.