Aiming at the design optimization problem of the current porous hydraulic buffer, including the buffer curve is not ideal and the influence of structural parameters is not fully considered, the mathematical model and AMESim simulation model of a porous hydraulic buffer were given. The main structure parameters of the piston diameter, return spring stiffness, annular gap, orifice spacing and aperture were simulated analyzed. According to the simulation results, the main structural parameters, orifice spacing and aperture were optimized based on genetic algorithm. It is shown that the peak pressure of the optimized buffer is reduced by 13%, and the average resistance is increased by 6%. The buffer curve is closer to the ideal buffer curve.