A FCC phenomenological-based model is presented in this study. This model accounts for the behaviour of the riser, the stripper and the regenerator. Both the reactor and the regenerator are incorporated in the model using detailed reaction kinetics. Catalyst regeneration allows for both catalytic and non-catalyzed combustion of CO to CO2, Overall, the model is constituted by a set of ordinary differential equations, relatively easy to solve, and suitable for steady and unsteady state simulation of FCC units. The proposed model avoids, as much as possible, empirical expressions being suitable for simulation of industrial FCC units and process control studies.