Based on the Kriging interpolation agent model,the performance of axial flow check valve was comprehensively optimized.The specific optimization objectives were as follows:to reduce forward flow resistance; to reduce vibration of the spool; to improve check performance.The main structure parameters affecting the forward flow resistance of the axial check valve were found through experimental design scheme.Taking them as optimization objects,the Kriging interpolation method was used to fit the sample points corresponding to the main structure parameters.In the case of ensuring fitting precision,NSGA-II genetic algorithm was used for the multi- objective optimization of the three main structure parameters.Three Pareto fronts were obtained.After weighing the influence of different factors on performance indexes,the structural parameters with the optimal comprehensive performance are finally obtained as follows:disc fullness coefficientα1=2.199,spool length L=386.322 mm,spool radius R =113.997 mm.The corresponding check valve performance is:forward outlet flow Q =161.839 kg/s,forward outlet flow rate v =3.302 35 m/s,check valve inlet pressure p =97 632.228 7 Pa. Compared with pre-optimization,the valve forward flow resistance is reduced by 1.2%,spool vibration is reduced by 0.24%,and check performance is improved by 2.3%.