To choose a more suitable turbulence model for the numerical simulation of the flow field in a cyclone separator, several turbulent models are compared and their flow fields are obtained with the help of numerical simulation. Comparing the numerical results with the experimental data, it has been found that numerical results with RSM (the Reynolds stress model) are better fitted to the experimental data than with the standard k-ε model. The RSM simulation results show that the vortex structure of a highly swirling flow, and SIMPLEC algorithm using RSM could be used to simulate the turbulence anisotropic behavior of a complex three-dimensional flow field.