In this study, zeolitic imidazolate framework-8 immobilized on aramid microfibrils (ZIF-8@AMF) with different crystal sizes were prepared in an aqueous solution at room temperature, and were used as adsorbents for the adsorptive removal of 1,4-dioxane from water. It was revealed that the immobilization of the ZIF-8 nanoparticles on the microfibrils improves the water permeation performance without impairing the adsorption performance.