Abstract: For improving the dynamic characteristic of accumulator and ensuring its robustness, the model of hydraulic braking system was developed by using AMESim. The brake number was taken as the optimization target, and the optimization tool was applied. The gas precharge pressure of accumulator was optimized using the genetic algorithms. The best inflation pressure was 6MPa, and the robustness of accumulator was verified. The research results provided the methodological and theoretic basis for match design of accumulator, which offers an important reference for improvement and optimization design of the accumulator.