Abstract: The excavating boom is subjected to complex forces and variable loads during the excavation process. It is difficult to obtain the load spectrum of the articulation point using actual measurement. To determine the fatigue life accurately under real working conditions, this paper utilizes the discrete element principle and EDEM-ADAMS coupled simulation method to analyze the excavation process of the excavator under different conditions. During the analysis, the load spectrum of each articulated point of the excavator boom is obtained under different excavation media and unbalanced loads. The stress and strain distribution of the excavator boom is then determined under different excavation conditions using Workbench software. The minimum fatigue life of the boom is calculated under various working conditions using the S-N fatigue life analysis method in combination with Ncode software. Additionally, areas prone to fatigue damage are identified for the excavator boom. The excavator boom fatigue life analysis accuracy is improved by using accurate material models under different working conditions. By reflecting the load spectrum obtained in actual working conditions, it provides the basis for reliability design.