Abstract: Detonation in suspended mixed RDX and aluminum particles in air was numerically simulated with the two-phase flow model. Formation and propagation of detonation was examined and the parameters of detonation were obtained. In calculation the diameter of RDX particle is 20.0 m. Numerical results show that aluminum particles added in high explosive dust can enhance the parameters of detonation waves. As the diameter of aluminum particles is 3.4 m, the ignition distances of two kinds particles are almost the same. As the diameter of aluminum particle is 7.0 m, the ignition distance of aluminum particles is much longer than that of high explosive particles, and a double front detonation can occur in the suspended mixed RDX and aluminum dust.