RDX dust detonation in suspension behind shock waves was analyzed with two-phase flow model. In the two-phase flow model,steady-state detonation regimes were studied on the basis of the mathematical model of detonation of RDX particles taking into account differences in velocities and temperatures of the mixture components. In this paper,pressure of detonation and development of temperature were numerically simulated when concentration of particle changed. Distribution of parameter was obtained and detonation of RDX dust-air in suspension didn′t arise if the concentration of particles was less than 0.076 kg·m^-3.