NOVELTY - A recycled swillcooked dirty oil treating method involves filtering impurity and removing acid from waste cook grease and waste fat oil. Carclazyte and phosphoric acid are added. The uniformly mixed substance is heated and decomposed. Phases are deposited and separated, and filtered to obtain liquid lipa and semi-solid carclazyte. The liquid lipa and the semi-solid carclazyte are added with cation performance activity emulsifying agent. The mixture is agitated to slightly emulsify fatty acid and triglyceride. Ionic catalytic stabilizing agent is added. Nitrogen is filled to obtain biofuel.    USE - Method for treating recycled swillcooked dirty oil.    ADVANTAGE - The method enables treating recycled swillcooked dirty oil in a simple manner and with low cost, less energy consumption and high efficiency.    DETAILED DESCRIPTION - A recycled swillcooked dirty oil treating method involves filtering impurity and removing acid from collected swill-cooked dirty oil, waste cook grease and waste fat oil. The swill-cooked dirty oil, the waste cook grease and the waste fat oil are put in a reaction kettle. 3-6% of carclazyte and 0.5-1.5% of phosphoric acid are added, and heated and uniformly agitated. The uniformly mixed substance is heated, settled and decomposed, and naturally cooled at 34-37 degrees C. Phases are deposited and separated, and filtered to obtain liquid lipa and semi-solid carclazyte, where a lipa acid value of the swill-cooked dirty oil, the waste cook grease and the waste fat oil is reduced from 3.5mg/koh/g to 0.9-1.4mg/koh/g. The semisolid carclazyte is naturally dried. The liquid lipa and the semi-solid carclazyte are put in the reaction kettle, and added with 3% of cation performance activity emulsifying agent. The mixture is high speed agitated at 50-80 degrees C for 20-50 minutes to slightly emulsify fatty acid and triglyceride. 0.1% of ionic catalytic stabilizing agent is added. Nitrogen is filled at speed of 0.5 cm3/s with 100-150 MPa for 15-25 minutes to obtain biofuel.