Abstarct: The most important purpose of blasting operations is useful fragmentation, because it involves a large part of production costs. So far, many empirical models have been presented in the field of prediction of fragmentation from the explosion. The models are presented in such a way that all relevant parameters cannot be considered together and simultaneously. Considering these constraints and conditions, new ways such as the Rock engineering system compensates the defects of the prediction of fragmentation from the explosion. In this thesis, Sungun Copper Mine was selected as a case study and eleven items of its explosions were used to construct the proposed model. These parameters include the Burden, Powder factor, the ratio of the spacing to the Burden (S/B), the ratio of the Stemming to the Burden (St/B), Stiffness ratio (H/B), the number of rows, the Time delay, the Blasthole deviation, the Hole diameter, , the ratio of the subdrilling to the Burden (J/B), number of joints, Joint aperture, Joint spacing, Joint persistence, Joint filling, Joint orientation, Uniaxial comperessive strenght of rock. Using these parameters, the fuzzy interaction matrix was formed and the rock fragmentation index was presented. The Goldsize image analysis method was used to determine the fragmentation quality. To validate obtained results between prediction and measured (real), determination coefficient (R2) and root mean square error (RMSE) index are chosen. R2 and RMSE are equal to 0.92 and 1.72. Also, according to the results obtained from the fuzzy interaction matrix, the parameters of Uniaxial comperessive strenght of rock and Joint orientation as the most important parameters on the system were obtained and The parameters of Burden, Powder factor, and the ratio of the spacing to the Burden are determined as parameters that have the greatest interaction in the system.