Fluent is a commercial CFD software.The flow field, heat transfer, combustion and chemical reaction can all be simulated by Fluent.In view of the complexity of dynamic hydrocyclone flow field, as an example, the Total type dynamic hydrocyclone separator was simulated. The physical model was simplified and established by Gambit software, and simulated through the fluent software by computer. The velocity field is obtained under cylindrical coordinate system, the tangential velocity, axial velocity and radial velocity of three velocity components cloud image. Through the study found that, the flow field of dynamic hydrocyclone was simulated and the complex flow problems can be solved by the fluent software. The simulation results can provide reliable basis to the process design and performance optimization for dynamic hydrocyclone, and also, it can save development cost, shorten the design cycle.