Based on the structure of a certain type of aviation axial-piston pump’s valve plate which adopts a pre-pressurization fluid path(consisting a damping hole,a buffer chamber,and an orifice)to reduce flow ripple,a single-piston model of the aviation axial-piston pump is presented. This single-piston model comprehensively considers fluid compressibility,orifice restriction effect,fluid resistance in the capillary tube,and the leakage flow. Besides,the instantaneous discharge areas used in the single-piston model have been calculated in detail. Based on the single-piston model,a multi-piston pump model has been established according to the simple hydraulic circuit. The single- and multi-piston pump models have been realized by the S-function in Matlab/Simulink. The developed multi-piston pump model has been validated by being compared with the numerical result by computational fluid dynamic(CFD). The effects of the pre-pressurization fluid path on the flow ripple and the instantaneous pressure in the piston chamber have been studied and optimized design recommendations for the aviation axial-piston pump have been given out. Based on the structure of a certain type of aviation axial-piston pump’s valve plate which holds a pre-pressurization fluid path (consisting of a damping hole, a buffer chamber, and an orifice) to reduce flow ripple, a single-piston model of the This single-piston model comprehensively considers fluid compressibility, orifice restriction effect, fluid resistance in the capillary tube, and leakage flow. In addition, the instantaneous discharge areas used in the single-piston model have been calculated based on the single-piston model, a multi-piston pump model has been established according to the simple hydraulic circuit. The single- and multi-piston pump models have been realized by the S-function in Matlab / Simulink. developed multi-piston pump model has been validated by being compared with the numerical result by computational fluid dynamic (CFD). The effects of the pre-pressurization fluid path on the flow ripple and the instantaneous pres sure in the piston chamber have been studied and optimized design recommendations for the aviation axial-piston pump have been given out.