A kinetic model for the deactivation of catalyst (based on a HZSM5 zeolite) in the transformation of methanol into gasoline is proposed from results obtained in an isothermal fixed bed integral reactor. The kinetic model takes into account the effect of the composition of the lumps of oxygenates, light olefins and rest of products on the catalyst deactivation along the reactor. The model allows for simulating the integral reactor and for studying the influence of the operating conditions on selectivity towards different lumps in the MTG process. The results have been experimentally proven in an isothermal integral reactor and are in agreement with the results of coke deposition along the reactor.