NOVELTY - Producing biodiesel, comprises (a) adding oil, fatty alcohols and solid base mixture comprising sodium silicate/calcium oxide/potassium fluoride and potassium fluoride/montmorillonite to kettle and performing transesterification reaction, heating in water bath, (b) placing the reaction mixture in conical retort, distilling fatty alcohols, and separating glycerol, and (c) adding at least one nonionic surfactant to the mixture of step (b) as a filter aid, separating fatty alcohols through ceramic membrane and obtaining high purity biodiesel.    USE - The method is useful for producing biodiesel (claimed).    ADVANTAGE - The method: provides biodiesel of high purity (claimed) in a simple and economical manner using easily available raw materials; avoids the accumulation of saponified products; and avoids vacuum distillation step.    DETAILED DESCRIPTION - Producing biodiesel, comprises (a) adding oil, fatty alcohols and solid base mixture comprising sodium silicate/calcium oxide/potassium fluoride and potassium fluoride/montmorillonite to the kettle and performing transesterification reaction, where sodium silicate/calcium oxide/potassium fluoride and potassium fluoride/montmorillonite mixture is present at 1-4 mass%, heating in a water bath and maintaining the reaction temperature in the kettle at 50-80 degrees C and a pressure of 2-6 MPa, where the molar ratio of fatty alcohols and oil is 8-15:1 and the reaction liquid hourly space velocity is 0.3-4/hour, (b) placing the reaction mixture in conical retort, distilling fatty alcohols, and separating glycerol, and (c) adding at least one nonionic surfactant to the mixture of step (b) as a filter aid, separating fatty alcohols through ceramic membrane and obtaining high purity biodiesel, where the hydrophilic-lipophilic balance of the non-ionic surfactant is 3-25, the nonionic surfactant is added at 0.1-10 mass% to step (a), the ceramic membrane support material is a ceramic, the film material is inorganic carbon, alumina or titania inorganic film, the ceramic membrane has a pore size of 0.02-1.4 mu m, and separation using the membrane is done at 10-120 degrees C and at a transmembrane pressure of 0.08-0.5 MPa.