Abstract: Based on the complex features of rotating gas-solid flow, the effects of injecting water,and the collision between particles and deposition efficiency,a 3-D mathematical model is established. The κ-ε/RNG model was used, and then the gas-solid flow characteristics and the deposition efficiency were simulated.The significant results were gotten:the initial position of the particles at the entrance of the separator and the particles diameter play an important role in particles moving feature.The sorption of water-film and ejecting water parameter would affect the particles motion and deposition efficiency.The suitable calculated equation of deposition efficiency for the water-film cyclone separator was given and the experiment results were also shown.