Gas-solid two-phase turbulent flows, mass transfer, heat transfer and catalytic cracking reactions are known to exert interrelated influences in commercial fluid catalytic cracking (FCC)riser reactors. In the present paper, a three-dimensional turbulent gas-solid two-phase flow-reaction model for FCC riser reactors was developed. The model took into account the gas-solid two-phase turbulent flows, inter-phase heat transfer, mass transfer, catalytic cracking reactions and their interrelated influence. The k-V-k(p) two-phase turbulence model was employed and modified for the two-phase turbulent flow patterns with relatively high particle concentration. Boundary conditions for the flow-reaction model were given. Related numerical algorithm was formed and a numerical code was drawn up. Numerical modeling for commercial FCC riser reactors could be carried out with the presented model.