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The adsorption of methanol in the acid sites of zeolites has attracted a great deal of attention because of its relevance to the industrial methanol to gasoline conversion process. In this work, the B3LYP hybrid density functional method was used to investigate the adsorption behavior of methanol on Bronsted acid sites in B, Al, Ga and Fe isomorphously substituted ZSM-5 zeolites. The optimized structures reveal a physisorbed methanol interacting with the zeolite framework through two hydrogen bonds. The order of the computed adsorption energy correlates with the acid strength of the isomorphously substituted ZSM-5:B-ZSM-5《Fe-ZSM-5＜Ga-ZSM-5＜Al-ZSM-5. The adsorption difference between methanol and ammonia is compared.