A closed Eulerian/Eulerian/Lagrangian mathematical model ( E/E/L model) for simulating the local flow characteristics of gas-liquid- solid three-phase fluidization systems was established by combining the Two Fluid Model ( TFM) and the Distinct Element Method ( DEM). This model was based on the fundamental equations of fluid mechanics. The motion of particles was described in the Lagrangian coordinates, while the gas phase and the liquid phase were dealt with in the Eulerian coordinates. Based on IPSA and PSIC solution techniques, the program of simulating gas-liquid-solid local flow was achieved. The predicted results of local gas holdup and local solid holdup as well as local axial liquid velocity agree with the corresponding experimental data of a gas-liquid- solid three-phase fluidized bed, and the applicability and reliability of this proposed model were validated.