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The discrete element simulation parameters calibration of pellet feed attrition was carried out by using EDEM simulation software, aiming at the lack of accurate attrition simulation model of pellet feed, so as to explore the damage mechanism of pellet feed in pneumatic conveying. The intrinsic parameters of pellet feed with a particle size of 2.50mm, which was used as the object and served for polyculture adult fish, were determined through basic experiments. The coefficient of restitution, coefficient of static friction and coefficient of rolling friction between feeds were determined to be 0.58, 0.23 and 0.12, respectively, while these three coefficients between feeds and soft plastics (soft PVC, polyvinyl chloride) were 0.69, 0.22 and 0.18, respectively through AoR (angle of repose) test of pellet feed, coefficient of restitution calibration test and discharge time of pellet feed, combined with the experimental optimization design method. The normal stiffness per unit area, shear stiffness per unit area, critical normal stress and critical shear stress were determined by uniaxial compression breakage test and simulation test of pellet feed, combined with response surface optimization, which were 2.25×109N/m3,8.05×108N/m3, 455MPa and 305MPa, respectively. The AoR simulation test and uniaxial compression simulation test were conducted with the determined parameters, whose results showed that the relative errors between the simulated value and the measured value in AoR, breakage force and discharge time were 0.35%, 1.43% and 2.81%, respectively;the contact parameters of the bonding model were verified by tests of free discharge, inclined sliding and inclined rolling, whose results showed that the contact parameters of the bonding model were reasonably set. The model developed could provide a method and theoretical basis for the calibration of discrete element simulation parameters and the study of attrition mechanism of pellet feed.