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The setting of contact parameters and contact model parameters between materials would directly affect the reliability of discrete element simulation test results. In order to determine the parameters of discrete element simulation of bulk manure in Xinjiang orchard, simplify the crushed irregular bulk manure into spherical particles, considering the cohesion characteristics between particles of organic fertilizer, the contact model of Hertz-Mindlin with Johnson-Kendall-Roberts was used in simulation modeling. The method of combining simulation and physical test was used to calibrate the discrete element parameters of bulk manure. Through the simulation of the combination of different parameters, with the accumulation angle as the response value, the Plackett-Burman test was used to screen the discrete element simulation parameters of bulk manure, and the parameters that had a significant effect on the stacking angle were obtained, that was, the restoration coefficient of manure and manure, the restoration coefficient of manure and steel plates, and JKR; the Box-Behnken design methods was employed to establish and optimize the second-order regression model of repose angle and significance parameter, in order to obtaine these optimal values such as the recovery coefficient between manure and manure, the recovery coefficient between manure and steel plate and the JKR were calculated as 0.49, 0.34, 0.02J/m2, respectively. Comparing the accumulation angle obtained from the simulation with the optimal parameter combination and the physical test value, the relative error was 2.73%. The results showed that the calibrated parameters were reliable, which provided a basis for the optimization of simulation parameters of the mechanization process of orchard bulk manure.