To solve the problems of conservative parameter setting, limited motion space, and insufficient simulation fidelity of the classic washout algorithm of the flight simulator. Based on the perception principle of the human vestibular system, the bandpass filtering shunt was introduced to redesign the structure of the classic algorithm, and the particle filter algorithm (PSO) was used to optimize the natural cut-off frequency of each channel filter of the washout algorithm before and after the structural improvement. Then, a joint simulation model is established in Matlab / Simulink. The results show that the two algorithms optimized by PSO have benign changes in perceived phase error and range of motion, and the improved washout algorithm has more obvious effects and better parameter optimization performance, effectively improving the dynamic fidelity of the flight simulator.