Abstract: The liquid-solid circulating moving bed reactor is a novel one, which consists of two or more reaction chambers and a particle transport system. Particles move down from the upper reaction chamber to the lower reaction chamber through an upper conduit and to the particle transport system through a lower conduit, then are lifted from the lower chamber to the upper reaction chamber through a riser.The circulating rate of particles and the flow of liquid in the two conduit are key to the continuous operation of the reactor.In this paper,the flow behavior of liquid in the conduits and particle circulation in the reactor are studied.At the same time the flow model is proposed and verified by experiment and simulation.