Abstract: The traditional design of RC parameter is based on the resonant equivalent circuit, which can not accurately describe the diode reverse recovery process, and it is difficult to optimize the RC parameters. Based on a lumped charge model for high-power PIN diode, the parameters of RC snubber are optimized with multi-objective optimization. Firstly, according to the topology and modulation mode of a three-level phase-shifted full-bridge converter, the influences of RC parameters on the reverse voltage spike of rectifier diode are analyzed. Secondly, based on the lumped charge model for high-power PIN diode, the simulation verification is performed by theoretical analyses. Then, multi-objective optimization design is used to design RC snubber. Finally, the experimental results verify the effectiveness of the optimal RC parameters to suppress the reverse voltage spike of rectifier diode.