Abstract: In order to tackle the troubles encountered in the operation of the clean coal crushing system of Xiaojihan Mine's coal washery, and to increase the coarse coal rate, an analysis is made of the present status of the existing crushing system. Based on the result of analysis, the schemes for structural optimization of the 0630 crusher are preliminarily proposed. Finally, the optimum scheme is defined through analysis using engineer discrete element method (EDEM). Practice shows optimization of the structure of the crusher has led to increase of the 45-6 mm coarse coal rate to 69.87 percent from 41.25 percent, drastic increase of sales revenues and reduction of equipment maintenance work and labor cost.