Honeycomb monolithic catalysts were used to convert efficiently vegetable oils to fatty acid methyl esters (FAMEs) as biodiesel fuels. Honeycomb monolithic catalysts were formulated by impregnating honeycomb gamma-alumina-wash-coated monolithic catalyst supports with various catalytically active metals such as ZnO, Na2O, MgO, and CaO. Canola oil in methanol was converted to FAME biofuels in a vertical honeycomb monolithic catalysts flow reactor to test catalytic activities and stabilities of formulated catalysts. Initial conversion of canola oil to FAMEs increased with decreased reaction temperatures, but catalytic activities of monolithic catalysts were deactivated severely at 250 degrees C. Catalysts deactivated at 250 degrees C can be regenrated by heating them in atmosphere for 4 h at 400 degrees C. Multi-layers of various active metals impregnated onto honeycomb monolithic catalyst supports stabilize and increase catalytic activities of monolithic catalysts. Order of loading catalytically active metals on honeycomb monolithic catalyst supports affects catalytic activities and stabilities of honeycomb monolithic catalysts. Calcium oxide stabilizes catalytic activities of formulated monolithic catalysts. Conversion of canola oil fluctuates repeatedly with increased reaction times in the honeycomb monolithic catalyst flow reactor. (C) 2014 Elsevier Ltd. All rights reserved.