NOVELTY - The method comprises proceeding distillation to a biodiesel rough product comprising biodiesel and heavy oil ester at a temperature of greater than biological diesel oil gasification temperature but less than heavy oil ester gasification temperature, collecting distillation obtained distillate, and wiping out an entrained entrainment of the distillation obtained distillate before collecting the distillation obtained distillate. The step of wiping out the entrained entrainment of the distillation obtained distillate comprises making the distillate to flow through a demister (20).    USE - The method is useful for refining biodiesel rough product.    DETAILED DESCRIPTION - The method comprises proceeding distillation to a biodiesel rough product comprising biodiesel and heavy oil ester at a temperature of greater than biological diesel oil gasification temperature but less than heavy oil ester gasification temperature, collecting distillation obtained distillate, and wiping out an entrained entrainment of the distillation obtained distillate before collecting the distillation obtained distillate. The step of wiping out the entrained entrainment of the distillation obtained distillate comprises making the distillate to flow through a demister (20). The distillation step is proceeded in a distillation tank, which is divided into a distillation section (11) and a distillate section (12), where the demister is located in the distillation tank. The demister is a wire mesh demister, which is a stainless steel wire mesh, where a volume weight of the wire mesh is 170-175 kg/m3. A ratio of volume and superficial area is 500-550m2/m3, and the void ratio is 97.5-98.1%. An inlet measure of the biodiesel rough product is 100-200kg/min.m2 relative to the 100 mm height mesh demister in the wire mesh demister. The pressure of the distillation is 0.5-1 kPa, and the temperature is 250-280 degrees C. An INDEPENDENT CLAIM is included for a refining system of a biodiesel rough product.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a biodiesel rough product refining system.    Distillation jar (10)    Distillation section (11)    Distillate section (12)    Demister (20)    Collecting plate. (31)