Abstract: An advanced hydrodynamic model, k-ε-k _p- ε _p- Θ two-phase flow model is established to simulate the gas-solid turbulent flow in riser reactor.The model,based on the kinetic theory of granular flow which recently is widely used to describe particle flow and simulates both gas phase and solid phase by low Reynolds number turbulent model taking into account the turbulent interaction between gas and particles.The model equations is coded and solved by CFX4 package,a CFD software developed by AEA Technology Company.The predicted results show satisfactory agreement with experimental data.Moreover the detailed analysis indicates that it is reasonable to add the particulate turbulent energy equation and its dissipation equation,and the closure method of the interactions between the turbulence of gas and that of particles is a crucial factor that influences the predicted results.