Abstract: 【Objective】 To calibrate the discrete element simulation model of silt in Xinjiang and quantitatively analyze the interaction between soil touching parts of agricultural machinery and soil. 【Methods】 EDEM discrete element simulation software was used, the contact parameters between soil and soil contact material（65 Mn） were calibrated by slope test, and the contact parameters between soil and soil were calibrated by stacking angle test. 【Results】 EDEM distance of slope was taken as the optimization objective, the regression analysis was carried out, and an optimal combination of discrete element model parameters between soil and 65 Mn was obtained： recovery coefficient 0.51, static friction coefficient 0.56, dynamic friction coefficient 0.08, JKR surface energy 4.12; Taking the stacking angle as the optimization objective, an optimal combination of discrete element model parameters between soils is obtained： recovery coefficient 0.57, static friction coefficient 0.65, dynamic friction coefficient 0.23 and JKR surface energy 4.49. The accuracy of the discrete element contact model was verified. The simulation test of slope test and stacking angle test was compared with the actual test. The errors of rolling distance and stacking angle were 6.05% and 1.28% respectively. 【Conclusion】 Under the conditions of the established simulation model, the relative errors between the plow body simulation test and the actual test were 5.69%, 5.95% and 6.49% at the working speeds of 8, 9 and 10 km/h.