In order to investigate the dynamic characteristics of the plunger cavity of the miniature axial piston pump and the influence of the plunger cavity force on the swash plate,based on the analysis of the plunger motion and the swash plate moment,a mathematical model was established and a simulation model of the miniature axial piston pump with seven plungers was built based on AMESim.The simulation analysis of the plunger cavity force was carried out from the plunger diameter,the plunger dead volume,the swash plate tilting angle and the plunger indexing circle diameter;the response surface optimization of the parameters affecting the plunger cavity force was carried out.The results show that the plunger cavity force and the swash plate overturning moment are significantly reduced after the optimization,and the optimized parameters can be used as the basis for the optimization of the plunger pump structure.