NOVELTY - Manufacturing automotive biodiesel fuel comprises testing oil of a material; pre-treating oil having acid value of more than 5.0 mg potassium hydroxide/g; performing ester exchange reaction on pre-treated oil or oil having acid value of less than 5.0 mg potassium hydroxide/g; separating solid base catalyst and glycerin; and continuously heating liquid introduced into a reduced pressure distillation system to 180-320 degrees C to perform reduced pressure distillation to obtain three fractions of biodiesel fuel and bottom product.    USE - Method of manufacturing automotive biodiesel fuel (claimed).    ADVANTAGE - The raw materials are easily available. The method is continuous and convenient to operate. The production period is short. The production efficiency is high. The equipment is highly universal. The investment is low. The three fractions of refined biodiesel fuel can be directly utilized without additive. The critical defects of high solidification point and narrow application range are overcome. A clean, green and reproducible energy source is achieved.    DETAILED DESCRIPTION - Manufacturing automotive biodiesel fuel comprises    (A) testing oil of a material, directly using oil having an acid value of less than 5.0 mg potassium hydroxide (KOH)/g for ester exchange reaction without need for pre-treatment and subjecting oil having an acid value of more than 5.0 mg KOH/g to pre-treatment;    (B) pre-treating by adding oil having acid value of more than 5.0 mg KOH/g, methanol and solid acid catalyst into a stainless steel reactor, heating to 60-65 degrees C to perform esterification reaction for 100-300 minutes, centrifuging to separate solid acid catalyst, and recovering methanol by distillation to obtain pre-treated crude oil;    (C) performing ester exchange reaction by adding pre-treated crude oil or oil having acid value of less than 5.0 mg KOH/g, methanol and solid base catalyst into an enameled reaction kettle, reacting at 55-63 degrees C for 50-100 minutes while stirring;    (D) separating solid base catalyst and glycerin, cooling by recirculated cooling water, centrifuging to separate solid base catalyst, separating heavy liquid and light liquid by liquid-liquid separator, introducing heavy liquid into glycerin refining unit to obtain glycerin, and introducing light liquid into a reduced pressure distillation system; and    (E) continuously heating liquid introduced into the reduced pressure distillation system to 180-320 degrees C to obtain three fractions of biodiesel fuel and bottom product.