Abstract: To obtain the dynamic load time history of the hinge points of the working device in the loader shovel loading operation process, and considering the gravity and inertia force of structure in the process of operation, a mathematical force model under the dynamic force balance was established based on the D'Alembert's principle, and the theoretical solutions of dynamic load of each hinge point were obtained. The dynamic load test method was proposed and the multiple parameters synchronous acquisition system was constructed, which contains the hinge force, cylinder pressure, cylinder displacement and boom structure stress. The experimental results show that the variations of the measured parameters on the boom are basically consistent. The finite element model of the boom structure is established. Comparative analysis of the values and the results show that the measured values are greater than the simulation values. The structural stress values obtained by the proposed method can accurately reflect the stress distribution of the working device. The simulation values and the measured values are consistent, which verifies the rationality of the mechanical model and the test method of the working device.