For the random vibration response of a micro satellite loaded antenna and S-flywheel supporting structure does not meet the criteria for system design of the micro-satellite based on integrated design concept, a co-supporting structure design of the satellite borne antenna and the flywheel was presented. The support structure sensitive point of random response RMS value as the optimization objective, the volume integral number and frequency constraints, the optimization mathematical model was established, the structure was optimized by using OptiStruct software, the support structure optimization treated by finite element analysis, the fundamental frequency reach 200 Hz, the quality is reduced by 65.6%; the vibration test of support structure performance was verified, the maximum relative amplification rate of x, y, z three direction acceleration response RMS value is 0.54. Results show that the optimization method is effective and feasible, and the supporting structure dynamic performance meets the requirements of a micro satellite design index optimization design well.