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The methanol–toluene alkylation process over zeolites catalysts offers a promising route for the production of <i>p</i>-xylene from low-cost feedstocks. Herein, we present a catalyst by preparing a core-shell aluminosilicate zeolite with an epitaxial silicalite-1 shell that passivates acid sites on the exterior surfaces. The <i>para</i>-selectivity was obviously increased due to the inhibition of the unselective isomerization of <i>p</i>-xylene over the external acid sites, and the open porous structure of the silicalite-1 shell ensured the mass transfer of reactants and products. Meanwhile, the carbon deposition was suppressed over HZSM-5@silicalite-1 catalysts, as a result of the decreased external acid sites. Furthermore, pulse chromatographic experiments revealed that the silicalite-1 coating could also improve the separation efficiency of <i>p</i>-xylene over <i>o</i>-xylene and <i>m</i>-xylene, due to the steric hindrance and extended diffusion path, resulting in a higher selectivity for <i>p</i>-xylene compared to that of the parent HZSM-5. The HZSM-5@4%S-1 catalyst showed the highest <i>p</i>-xylene selectivity (>80%) and methanol efficiency (66%), with good catalytic stability throughout the 170 h reaction time.