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Due to the lack of accurate simulation model parameters in the process of mechanized harvesting and crushing of cotton straw, there is a great difference between the simulation effect and the actual operation in the design of machinery and tools, which limits the design and research of cotton straw harvesting and crushing device to a certain extent. Xinjiang cotton straw was used as experimental material to carry out simulation analysis. After the intrinsic parameters of cotton straw were determined by physical tests, the EDEM simulation software was used for test simulation and parameter calibration of cotton straw. The accumulation angle and the maximum destructive power of cotton straw were 28.62°and 143.21N respectively by the method of accumulation angle test and bending test. The Hertz-Mindlin no slip model and Hertz-Mindlin with bonding model were used to simulate the stacking angle and bending of cotton straw. The collision recovery coefficient, static friction coefficient and rolling friction coefficient between cotton straw and the collision recovery coefficient, static friction coefficient and rolling friction coefficient between cotton straw and steel were respectively 0.5, 0.41, 0.06, 0.5, 0.37 and 0.08, and the normal contact stiffness, tangential contact stiffness, critical normal stress and critical tangential stress of cotton straw were respectively obtained, which were 4.15×1010N/m, 5.60×1010N/m, 40MPa and 50MPa, respectively. According to the above results, the pulverized cotton straw can be divided into powder type material, crushed type material and unbroken type material according to different lengths and widths. The deviation between the simulation test quality and the actual test quality was 6.84%, 8.29% and 7.37%, which proved the feasibility of the parameters and can be used for the parameter calibration of cotton straw.