In order to optimize the elicitation performance of the elicitor of the hydrogen recirculation system of a proton exchange membrane fuel cell in the low‑power region，structural parameters of the elicitor of a 40 kW‑class fuel cell were simulated.Univariate influence tests were carried out at a given power to investigate the influence of nozzle throat diameter，mixing chamber diameter，mixing chamber length and the distance between the outlet of nozzle and the inlet of the mixing chamber on the performance of the ejector.The orthogonal tests were carried out by selecting the better three parameters from each of the four factors mentioned above，and the extreme deviation of the test results was analyzed to get the optimal combinations of the parameters mentioned above and the sequence of the degree of influence on the ejection performance of the ejector.Finally，the optimized ejector was simulated.The results show the maximum hydrogen reflux ratio of 2.315 is obtained when the nozzle throat diameter，mixing diameter，mixing chamber length，and the distance between the outlet of nozzle and the inlet of the mixing chamber are taken as 0.8，3.0，18，2.5 mm，respectively，under the working condition of 60 A.The results of the study show that among the four parameters mentioned above，low power condition has a significant effect on the ejection coefficient，while low power condition has a significant effect on the ejection coefficient，and low power condition has a significant effect on the ejection coefficient.Among the four parameters mentioned above，the parameter that has the greatest influence on the ejection coefficient under low power condition is the nozzle throat diameter，and the parameter that has the least influence on the ejection coefficient is the distance between the outlet of nozzle and the inlet of the mixing chamber.The results of the study provide a reference for the optimization of the structural parameters of the ejector under low‑power working conditions.