Multi-scale model considered the heat transfer, mass transfer, momentum transfer, fluid flow with reactions together at different spatiotemporal scales for the riser reactor of secondary reactions of fluid catalytic cracking gasoline (SRFCCG) process has been preformed in this work. Micro-scale of kinetics in catalyst particles, meso-scale of clusters, voids, dense phase, dilute phases, and heterogeneous structures in gas-solid flow, and the macro-scale of product distribution over riser reactor have been established using multi-scale modeling method and integrated by the multi-domain strategy. The proposed model was solved with the software of EQUATRAN-G. Good agreement between simulation results and the experimental data suggested that the proposed model was well constructed and simulation exercise was successful. The multi-scale model was capable of predicting heterogeneous structures of multi-phase flow, reactor temperature profile, and product distribution of SRFCCG process. (C) 2009 American Institute of Chemical Engineers AIChE J, 55: 2138-2149, 2009