eing renewable and clean-burning, biodiesel, originated from triglyceride oils/fats, get relevance over conventional diesel fuels. Among the different triglyceride sources, waste cooking oil has high significance in terms of price and effective use of waste material. Highly reusable sodium titanate nanotube catalyst is developed here from porous titania and NaOH via wet impregnation method for its catalytic application in biodiesel production by the transesterification of waste cooking oil with methanol. Here, NaOH is incorporated into the porous sol-gel derived TiO2 prepared in the presence of a nonionic surfactant in an aqueous solvent. The X-ray diffraction pattern of the catalyst indicated Na2 Ti3 O7 as the active crystalline phase of the material responsible for catalysis. XPS analysis confirmed the formation of Na2 Ti3 O7 , whereas TEM analysis revealed the porous nanotubular morphology. Investigation of the effect of reaction variables on catalytic performance indicated the viability of the catalyst in a range of mild reaction conditions. The catalyst showed excellent activity and gave a fatty acid methyl ester content of 100% under the selected reaction conditions of catalyst weight of 4 wt% of oil, methanol/oil molar ratio of 15:1 at the reaction temperature of 65 °C for 1.5 h reaction. Catalyst leaching and loss of activity in repeated cycles are one of the most inevitable hurdles in biodiesel catalysts, but here, no loss in the activity was detected even up to five repeated cycles of catalysis, demonstrating the efficiency and stability of the present catalyst. The prepared biodiesel met the various specifications stated in the biodiesel standard, mainly United States biodiesel standard ASTM D6751 and European biodiesel standard EN14214, claiming its safe use as fuel in diesel engines.