A complete model for prediction performance of an oxidation air-lift reactor has been developed. The model includes reaction kinetics, flow configuration, mass transfer and hydrodynamics. Liquid bulk and gas phases are modeled using a cell model. The mass transfer tares are computed from the film model. Hydrodynamics parameters are calculated with an adequate model based on balance equations and on experimental data. The model predicts the variations of concentrations and hydrodynamics parameters along the reactor and hence is able to provide a good description of the reactor.