NOVELTY - Continuous industrial method for producing biodiesel fuel involves: (a) interesterification step: providing a source of triglyceride; mixing triglycerides with methyl or ethyl ester with up to 6 carbon atoms, or its mixtures; (b) recovering phase of ethyl acetate: heating the solution from the second filter by heat exchange with distilled biodiesel and feeding end to a first vertical evaporator having an expander head at the top; and (c) separation stage and obtaining biodiesel.    USE - The continuous industrial method is useful for producing biodiesel fuel.    ADVANTAGE - The continuous industrial method can optimize power consumption; and can reduce use of thermal energy and operational costs.    DETAILED DESCRIPTION - Continuous industrial method for producing biodiesel fuel involves: (a) interesterification step: providing a source of triglyceride; mixing triglycerides with methyl or ethyl ester with up to 6 carbon atoms, or its mixtures, and adding to this solution a premix of a methyl or ethyl ester with up to 6 carbon atoms, or its mixtures, and a strong base such as sodium methoxide as catalyst; heating the resulting mixture at 20-120 degrees C and sending to a reactor for ultrasonic cavitation; vacuum filtering the solution from the second reactor and recycling the solid catalyst retained by the filter to premix with the methyl or ethyl ester; adding the required amount of formic acid to the filtrate to obtain a solution pH ranging from 6.5 to 7.5; and filtering the neutralized solution in a second filter;(b) recovering phase of ethyl acetate: heating the solution from the second filter by heat exchange with distilled biodiesel and feeding end to a first vertical evaporator having an expander head at the top; use vapors of methyl or ethyl ester from the first evaporation step to heat the second evaporator; and (c) separation stage and obtaining biodiesel: distilling the solution coming from the flash distillation through a short path distillation in distillation columns arranged in series; recovering in parallel the light phases of distillation columns, i.e. biodiesel, cooling down by heat exchange with the solution entering the recovery system; recovering the heavy phase, i.e. glycerides of modified structure, from the distillation columns and sending to a final storage tank.