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In order to solve the problem that there is a lack of accurate and reliable discrete element interaction model of seed furrow soil-seed-covering device in the study of the micro-movement law of seed furrow soil and seed in the operation of covering device of planter. Taking the cohesive soil with moisture content of （15.7±0.25）% as research object, the relevant parameters and models were calibrated based on EDEM. The traction resistance of soil covering operation was taken as the response value. Based on Plackett-Burman test, the parameters sensitive to traction resistance were selected as soil-soil rolling friction coefficient, soil-65Mn static friction coefficient, critical normal stress and critical shear stress. The range of values for each sensitive parameter was determined based on the steepest ascent test. Based on Box-Behnken experimental optimization, the values of soil-soil rolling friction coefficient, soil-65Mn static friction coefficient, critical normal stress, and critical shear stress were obtained as 0.15, 0.31, 18.45kPa, and 18.58kPa, respectively. Secondly, taking soybean seeds as example, the discrete element interaction model of seed furrow soil-seed was established. The collision recovery coefficient, static friction coefficient and rolling friction coefficient between seed furrow soil and soybean seeds were taken as the experimental factors. The simulation stacking angle was taken as the evaluation index. Through the optimization of Box-Behnken test, the values of each test factor were 0.57, 0.33, 0.08, respectively. Finally, the discrete element interaction model of seed furrow soil-seed-covering device was established, and the experimental verification was carried out. The results showed that the average relative error between the simulated and measured values of traction resistance was 2.22%. The relative error between the simulated and measured values of the stacking angle was 1.61 %. The relative errors between the simulated and measured values of soil cover thickness and seed spacing variation coefficient were 4.89% and 5.90%, respectively. They were all small. The established discrete element interaction model of seed furrow soil-seed-covering device was accurate.