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In response to the lack of effective discrete element model for the simulation analysis of the interaction between soil-engaging components and soil in disturbed saturated paddy soil environment, the disturbed saturated paddy soil with high moisture content, high rheology and high adhesion was taken as the research object. A two-phase mixing model of soil particles and water particles was established by using the Hertz Mindlin with JKR contact model in EDEM software. The discrete element parameters of the disturbed saturated paddy soil model was calibrated through slump tests and soil bin tests. With the slump flow was the experimental indicator, the Plackett-Burman experiment was used to screen out three parameters from eight relevant parameters, namely, the soilwater JKR surface energy, the soil-soil rolling friction coefficient and the soil-soil recovery coefficient. The soil-water JKR surface energy and the soil-soil rolling friction coefficient had a highly significant influence on the slump flow, and the soil-soil recovery coefficient had a significant influence on the slump flow. A second-order regression model of the slump flow and significance parameters was established and optimized based on the Box-Behnken experiment. The results of variance analysis of single factor showed that the soil-water JKR surface energy had a highly significant influence on the slump flow, and the soil-soil rolling friction coefficient had a significant influence on the slump flow. The interaction between the soil-soil recovery coefficient and the soilsoil rolling friction coefficient had a significant influence on the slump flow. Furthermore, the optimal parameter combination was obtained as follows： the soil-soil recovery coefficient was 0.402, the soilsoil rolling friction coefficient was 0.136, and soil-water particles JKR surface energy was 0.920 J/m2.The traction resistance of sliding plate of the rice seeder during its movement in disturbed saturated paddy soil as the indicator, a simulation of the interaction between the sliding plate of the rice seeder and the disturbed saturated paddy soil was conducted based on the calibrated parameter combination, and verified by the soil bin test. The results showed that the average value of traction resistance of the sliding plate in the simulation was 130.239 N, and the average value of traction resistance in the soil bin test was 139.231 N. The resistance value error of the sliding plate model obtained from the simulation and test was 6.46%. The discrete element simulation of the disturbed saturated paddy soil was consistent with the test, indicating that the parameter calibration method was accurate and feasible. The discrete element model of disturbed saturated paddy field soil established can provide technical support for the study of the interaction between soil and soilengaging components.