NOVELTY - Production of biodiesel comprises dehydrating vegetable oil; esterifying by adding methanol and sodium hydroxide; recovering methanol in the esterified vegetable oil; neutralizing by adding 10-15% sodium carbonate solution at 70-80 degrees C; distilling neutralized vegetable oil and collecting the esterified vegetable oil with boiling point of 170-210 degrees C; and adding cetane modifying additive in the distilled vegetable oil and filtering, where weight ratio of distilled vegetable oil and cetane modifying additive is 1:0.001-0.003.    USE - Method of producing biodiesel (claimed).    ADVANTAGE - Compared with existing technology, the reaction tank, distilling kettle, and other device used in the method of producing biodiesel are common chemical equipments, thus does not need much investment cost. The method has abundant raw material sources, simple and short production method, and low cost; and produces no environmental pollution. It guarantees energy safety.    DETAILED DESCRIPTION - Production of biodiesel comprises:    (A) dehydrating by putting vegetable oil into reaction kettle; heating to 80-105 degrees C; and keeping warm until the moisture concentration in vegetable oil is less than 1 pt.wt./thousand pts.wt.;    (B) esterifying by adding methanol and sodium hydroxide into dehydrated vegetable oil; reacting at 60-90 degrees C under 0.04-0.06 MPa, until the generated product acid value is less than 5, where weight ratio of vegetable oil, methanol, and sodium hydroxide is 1:0.6-1.5:0.01-0.05;    (C) recovering methanol in the esterified vegetable oil;    (D) neutralizing by adding 10-15% sodium carbonate solution in the esterified vegetable oil at 70-80 degrees C; stirring for 5-10 minutes; stop stirring; waiting for 1-2 hours; opening the valve at the bottom of the reaction kettle; and discharging the water layer, where weight ratio of vegetable oil and 10-15% sodium carbonate solution is 1:0.3-0.5;    (E) distilling neutralized vegetable oil and collecting the esterified vegetable oil with boiling point of 170-210 degrees C; and    (F) adding cetane modifying additive in the distilled vegetable oil; and filtering, where weight ratio of distilled vegetable oil and cetane modifying additive is 1:0.001-0.003.