Abstract: In order to obtain the discrete element simulation parameters of straw biochar,the contact parameters of biochar are calibrated by combining simulation analysis with physical experiment. The Placket-Burman test is used to screen out the biochar discrete element significant influence parameters and the steepest climb test is used to determine the optimal interval of the significant parameters,as well as the Box-Behnken test is applied to determine the three significant parameters,the tests results shows that the values of significant parameters for charcoal-charcoal rolling friction coefficients,surface energy JKR（J/m~2）and charcoal-steel rolling friction coefficient are 0.097,0.018,and 0.256 respectively. The comparison of Rocky simulation results and the stacking angle test points out that the error of the specified parameters is 2.33%,which meets the setting requirements of the simulation analysis parameters.