TECHNOLOGY FOCUS - CHEMICAL ENGINEERING - Preferred Properties: The methanolysis reaction is carried out at 370-500 degrees C, preferably 440-460 degrees C and pressure of 10-30 MPa, preferably 17-19 MPa.    TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Component: The material supply unit has a liquid feeding pipe (240) to supply the mixture of raw material to the reaction tank. The liquid feeding pipe comprises a liquid feeding unit (i) to liquid-feed animal and vegetable fats or its waste edible oil, and a liquid feeding unit (ii) to liquid-feed methanol. The liquid feeding unit (i) and liquid feeding unit (ii) liquid-feeds raw material at the same time. The material supply unit further has a drive unit (230) which synchronizes and drives the stroke of piston of the liquid feeding unit (i), and stroke of piston of the liquid feeding unit (ii), a liquid feeding unit (iii) to liquid-feed animal and vegetable fats or its waste edible oil for liquid feeding unit (i), and an oil-pressure-adjustment unit to adjust oil pressure of the animal and vegetable fats or its waste edible oil liquid-fed by the liquid feeding unit (iii). The liquid feeding unit (i) liquid-feds animal and vegetable fats or its waste edible oil to which oil pressure is adjusted by the oil-pressure-adjustment unit. The drive unit has a rotation unit, a crank (a) and a crank (b) provided on the rotating shaft rotated by the rotation unit, a crank connecting rod (I) in which an end is connected with crank (a) and the other end is connected with the piston of the liquid feeding unit (i), and a crank connecting rod (II) in which an end is connected with crank (b) and the other end is connected with the piston of the liquid feeding unit (ii). The reactor has a drive unit (d1) to transmit a drive to the stirring unit with a non-contact system. The biodiesel fuel producing apparatus further has a heat exchanger (400) to cool the reaction mixture discharged from the reactor by heat-exchanging with the raw material before flowing into the reactor, and a gas-liquid separator (500) to vaporize reaction mixture discharged from the reactor, and separates a biodiesel fuel and unreacted methanol.