NOVELTY - The apparatus comprises a methoxide supply unit for supplying methoxide with a catalyst, alcohol and sodium hydroxide, and a reaction/separation section for reacting the mixture and separating the biodiesel. The methoxide supply unit is installed inside a first tank and includes a methoxide vent. A material supply opening is formed in an upper part of the methoxide supply unit to supply the catalyst and alcohol. A first air nozzle is installed at a bottom surface of the first tank. A first temperature sensor is installed inside the first tank and detects the temperature of the first tank.    USE - The apparatus is useful for manufacturing bio-diesel (claimed) that is used in a diesel engine.    ADVANTAGE - The apparatus rapidly manufactures the bio-diesel in an efficient manner with reduced time period.    DETAILED DESCRIPTION - The apparatus comprises a methoxide supply unit for supplying methoxide with a catalyst, alcohol and sodium hydroxide, and a reaction/separation section for reacting the mixture and separating the biodiesel. The methoxide supply unit is installed inside a first tank and includes a methoxide vent. A material supply opening is formed in an upper part of the methoxide supply unit to supply the catalyst and alcohol. A first air nozzle is installed at a bottom surface of the first tank. A first temperature sensor is installed inside the first tank and detects the temperature of the first tank. A glycerin vent discharges the glycerin of the sub-layer produced in the lower part through the reaction of the methoxide. A biodiesel vent inhales the biodiesel. A second temperature sensor is installed inside a second tank and detects the temperature of the second tank. The reaction/separate unit comprises a refining part for filtering the foreign substance using a filter. The refining part comprises a filter that is accommodated inside an outer tube to filter the foreign substances from the biodiesel. A connecting rod is formed in a lower part of the refining part for discharging the biodiesel. A debris discharging pipe is arranged a bottom surface of an outer container for discharging the precipitated foreign substance.