Abstract: Taking the design and optimization of active suspension as an example, based on the idea of multidisciplinary design optimization, a multidisciplinary design optimization method was proposed with the control discipline in loop, bring the control discipline into the optimization loop of the system. To achieve better overall optimal results, the collaboration between the system's structural design and control discipline was fully considered. And a quarter-vehicle active suspension model and the LQG controller model were established. Based on the optimization framework of the multidisciplinary feasibility method, multi-disciplines analysis was conducted, and the suspension parameters and controller parameters were optimized at the same time. The optimization results show that this method can coordinate the coupling relationship between suspension dynamic and control discipline to obtain the global optimal solution. The optimized active suspension can reduce the root of mean square (RMS) of vertical body acceleration by 27% under the premise of not consuming more energy, and can ensure that the suspension's working space and tire deformation are within a certain range.