Abstract: A two-dimensional mesoscale model of mixed explosives was established in this paper to analyze the influence of graphite to the detonation propagation and detonation performance of the mixed explosives. The simulation of the detonation propagation of mixed explosives with different graphite content and granularity shows that the internal pressure of graphite particle and the pressure of explosive around the graphite particle both increase in the direction of the detonation propagation and form a special distribution of flow field of detonation pressure. It also can be seen that the calculated result of the detonation velocity is consistent with the experimental regularity.