Abstract: The goat rib is the main obstacle in the process of automatic goat carcass segmentation. A scientific and reliable discrete element model of goat rib can provide both the analysis of mechanized goat carcass segmentation process and the optimization of tool parameters with the theoretical basis. The Hertz-Mindlin with bonding model (HMB), which can simulate the bonding between the particles, was selected to build the model of goat rib because of the tight bonding property of goat rib before crushing. In order to obtain the scientific and reliable discrete element model of goat rib, the measurement and calibration of basic physical parameters, contact parameters, and bonding parameters of goat ribs were essential. Therefore, the Boer goat, which was representative in the world, was selected as the research object, and the tests and simulations were carried out to complete the calibration of simulation parameters. In the first step, the ribs from the Boer goat carcass were properly treated to obtain the rib samples which were suitable for various tests. Then the outline size, density, Poisson’s ratio and shear modulus of the goat rib were obtained by instrument measurement, drainage test and uniaxial compression test. The basic simulation parameters of steel were obtained by consulting the relevant data. Next, the contact parameters such as static friction coefficient, rolling friction coefficient and collision recovery coefficient were obtained through collision tests, inclined plane friction tests and friction coefficient measurement tests. The bending failure test of the goat rib was carried out on the texture analyzer to obtain the peak failure force and cutting situation, which were used to be the target value of the simulation test. According to the actual test conditions, using Hertz-Mindlin with bonding model in EDEM simulation software, the discrete element model of goat rib is established and the bending failure simulation test was carried out. Since there was no research on bone bonding parameters, the path of steepest ascent was used to find the optimal parameter range which included the optimal value of bonding parameters. Based on the results of the path of steepest ascent, a central composite design and corresponding response surface analysis were used to create a quadratic polynomial model between the peak failure force and the four bonding parameters. The coefficient of determination by the quadratic polynomial model was 0.9011, which could indicate that the model was reliable. Under the condition that the model was significant and the lack of fit was not significant, the terms that did not significantly affect the results were removed, and the regression model was optimized to obtain a new quadratic polynomial regression model. After completing the optimization of quadratic regression model and the regression equation, the parameter combination of four significant influencing factors were obtained by solving the regression equation. The results illustrated that the normal stiffness per unit area was 7.07×10¹³ N/m³ , the shear stiffness per unit area was 6.22×10¹² N/m³, the critical normal stress was 1.34×10⁸ Pa, critical shear stress was 1.87×10⁸ Pa. Finally, the discrete element bending failure simulation test of five goat ribs with different dimensions was carried out based on the calibrated optimal values of the discrete element parameters to verify the accuracy and reliability of calibration results. The two data of failure forces between the physical experiment and simulation with the optimal calibration parameters were very similar, which telling us that the average relative error was 4.19% and the max relative error was less than 6.49%. The results of contrast experiment showed that the calibration results and the discrete element model of goat rib were credible. The study in this paper can provide a theoretical basis for both mechanization of goat rib segmentation and the parameter optimization of segmentation tool.