The invention provides a preparation method of an alveolate cordierite cerium oxide nanotube desulfurizing agent. The preparation method comprises the following steps of (a) preparing a zinc oxide nanorod array by taking alveolate cordierite as a base, namely respectively preparing a zinc nitrate and a hexamethylenetetramine solution, uniformly mixing in an isopyknic manner, immersing an alveolate cordierite base in the mixed solution, carrying out hydro-thermal synthesis at 90 DEG C-200 DEG C so as to obtain a zinc oxide nanorod array through preparation; and (b) preparing the alveolate cordierite cerium oxide nanotube desulfurizing agent, namely placing the cordierite base of a growing zinc oxide nanorod array into a cerous nitrate solution, and carrying out hydro-thermal synthesis on the cerous nitrate solution at 90 DEG C-160 DEG C. The method provided by the invention has the advantages that a cerium oxide nano-structure is loaded on the surface of the alveolate cordierite, the composite catalyst has the high specific area and the uniform dispersibility, the specific surface area and the reactivity of the catalyst are preferably improved, and a desulfurization property is improved.