Due to the characteristics of the new process for manufacturing glass mat reinforced thermoplastic(GMT) sheets, the way of dilute spout-fluid bed was proposed. Particle velocity distribution in the bed was measured to investigate the influence of manufacturing conditions and structure of the bed. The results show the particle velocity in the annulus area in this equipment is about an order of magnitude higher than that in ordinary spout-fluid beds; the particle velocity distribution is significantly influenced by the spout gas flow and the fluid gas flow. The draft tube and the nozzle diameter can be used to modify this distribution. Flow regimes in pilot spout-fluid bed were studied. This could be useful to the development, design and operation of the new process.