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Rice bud seeds exhibit different physical properties from other crop seeds as high moisture content and large length difference of rice buds. Therefore, it is essential to calibrate the main discrete elements contact parameters of rice bud seeds with different moisture contents, and reduce the simulation system error that caused by inaccurate parameters of rice bud seeds. Three main contact parameters were calibrated, including coefficient of static friction between bud seeds and stainless plate (X1), coefficient of static friction between bud seeds (X2) and coefficient of rolling friction between bud seeds (X3), through experimental determination combined with simulation test of rice bud seeds friction angle. Two dynamic repose angles α and β and slipping friction angle γ were formed with three devices, and measured with the software InSight Explorer based on image processing technology. Then through discrete element simulation test of bud seeds frictions with EDEM, the ternary regression equation between the three coefficients X1, X2 and X3 and the three friction angles was established. The experimental results of the three frictions were the correction index, and the regression equation was numerically solved to obtain the three main content parameters. The verification test of the calibration parameters showed that the relative error between simulation and experiment results of the bud seeds friction angles with different moisture contents was less than 2.75%. So the discrete element model of rice bud seeds and the actual particle material reflected the same friction characteristics, and the regression model satisfied the calibration requirements for bud seeds parameters with different moisture contents. Furthermore, the relative error of the other variety rice bud seeds was less than 5.54%, which indicated that the calibrated discrete element model and contact parameters of the bud seeds can be applied to the dynamic simulation of the precision sowing device.