Sulfided ruthenium supported catalysts based on an Al pillared montmorillonite, with different Al contents, have been prepared and characterized by XRD,S-BET, TEM, XPS, and tested in the hydrodesulfurization (HDS) of dibenzothiophene (DBT). The role of the Al content in the catalytic activity of RuS2 based catalysts was studied. The activity and selectivity of the catalysts studied in the HDS of DBT suggest that Al pillared montmorillonite could be of interest as a low cost support for this reaction. (C) 2011 Elsevier B.V. All rights reserved.