Abstract: The effects of alkali-treatment and alkali-acid-treatment of ZSM-5 on the catalytic properties and catalytic performance of benzene alkylation with methanol were studied. The results showed that alkali treatment of ZSM-5 can remove the extra-framework Si species to enhance the diffusivity. However, it can also neutralize the strong acid sites of ZSM-5 and weaken the activation of methanol, reducing the reactivity of benzene alkylation with methanol. The twice acid treatment of alkali-treated ZSM-5 improve the catalytic performance because it can not only remove the extra-framework Al species, but also restore a part of strong acid sites neutralized in the process of alkali-treatment. Further research on the effects of alkalinity showed that the extra-framework Al species and Si species can be removed and a moderate particle size can be obtained after treatment of ZSM-5 with a moderate concentration of alkali. Moreover, the carbon deposition rate has been slowed down due to a decrease of strong acid sites. Therefore, the conversion of benzene can be improved by more than 15%.