The simulation of particles residence time distribution (RTD) in a gas-solid cyclone reactor (GSCR) based on the CFD-DDPM tracer method was conducted. The comparison between the computed results and the experimental data shows that this model is applicable to predict the gas-solid hydrodynamics with better accuracy. Simulated results depict that the predicted particles RTD will be more accurate if a lower sampling duration is applied. Reynolds number, particulate loading and Stokes number have significant effects on the shape of RTD curves. The appearance time of the first peak in the diffusion chamber is not affected by Reynolds number, but the peak height diminishes with the increase of Reynolds number. A particle with a higher Stokes number descends faster and has a shorter residence time. As particulate loading increases, the appearance time of the first peak shifts left along the X-axis. The agglomeration and separation chamber MRT are sensitive to the change of Reynolds number, particulate loading and Stokes number. (C) 2020 Published by Elsevier B.V.