In order to reduce the quality of the direct drive turntable to prevent inertia from affecting its machining accuracy,the dynamic and static characteristics analysis,response surface construction,sensitivity analysis and NSGA-II genetic algorithm optimization were carried out;the machining parameters before and after optimization were contrasted and analyzed.The results show that by using the optimized parameters,not only the machining requirements can be better met,but also the stiffness and the first natural frequency of the direct drive turntable can be improved significantly,and the quality of the direct drive turntable can be reduced significantly.