Objective To design vehicle automatic palletizing equipment for small and medium- sized chemical fertilizer plants and to analyze the dynamic stability of the equipment. Methods Lagrange kinematics equation was applied to obtain the driven force of cart mechanism and trolley mechanism, which generated excitation oscillation of the lifting arm, and the structural dynamics theory was used to attain the equations of the lifting arm incentive motion. Besides, simulation analysis was conducted for the influence of the key design parameters. Conclusion The designed time parameter for completing an action of the cart mechanism and trolley mechanism had a great effect on the dynamic stability of the equipment. The smaller the diameter of the lifting arm connecting component, the lower the dynamic stability of the equipment. Using different steel materials to for the lifting arm connecting component had basically the same effect on the dynamic stability of the equipment.