Using original hydrothermal technology honeycomb corundum monoliths with a peculiar porous structure and high water-adsorbing capacity facilitating procedures of active component loading have been produced. The detailed study of ethanol steam reforming over Ru/Ce_0.5Zr_0.5O₂(CZ), Ru/Ce_0.4Zr_0.4Sm_0.2O₂–(δ + γ)Al₂O₃ (granulated) and Ru/Ce_0.4Zr_0.4Sm_0.2O₂/α-Al₂O₃ (monolithic) has been performed. It has been revealed that the main route of the reaction over Ru/CZ is ethanol dehydrogenation while ethanol dehydration into ethylene mainly occurs over Ru/CZS–Al₂O₃. Variation of the H₂O–EtOH ratio, contact time and temperature allows hydrogen and CO yield to be governed. The monolithic catalyst has shown a high performance and stability at short contact time (0.1–0.4 s) and low water concentration (H₂O–EtOH ∼ 1–3).