Abstract: In order to find the weak links in the precision CNC grinder, the modal analysis and harmonious response analysis were used to identify the vertical plate as the key component to be optimized. Firstly, the topological optimization method is used to optimize the material distribution of vertical plate. Then, the maximum deformation, mass and first-order natural frequency of the vertical plate are taken as the optimization objectives, and the response surface method is used to conduct multi-objective optimization of the vertical plate. The optimal Pareto solution is calculated based on the multi-objective genetic algorithm. Finally, the maximum deformation of the vertical plate is reduced by 3.83%, the mass is reduced by 25.35%, and the first-order natural frequency is increased by 22.33%. At the same time, the amplitude of the grinder in all directions is also reduced, and the dynamic performance of the machine is improved.