Abstract: A high-Reynolds two-phase round turbulent jet was numerically simulated by means of large eddy simulation for gas-phase and particle trajectory model for particle-phase.The dispersion behavior of particles with median Stokes number in large scale structures was studied.Two-phase statistical velocities were compared with each other.It's shown that particle dispersion is dominated both by large eddy structures and particle inertia,resulting in a high particle concentration distribution in the edge of vortex structures or interlaced regions of vortexes(called as particle preferential distribution).The decaying rate of two-phase velocity in the axial direction is different,and the particle-phase velocity decays slower than that of gas-phase.In the near field,two-phase velocities differ from each other significantly.In the far field,two-phase mean velocities are similar,and particle velocity decays radially slower.