LYE series oil filter machine can treat with regeneration of waste engine oil. It not only removes the impurities, water, and acid matter, organic and inorganic acid effectively, but also can remove carbon particulate matter and peroxides. In engine oil, bitumen and colloid and other sludge can be removed similarly. After treatment by the machines, the color of the treated oil is recovered and the quality indexes are improved too so as to resume the performance of engine oil, to keep the engine in good lubricating conditions, to guarantee lubricating system of engine to work properly and to prolong the service life of engine and oil, finally, to economize expense on oil purchasing and save oil resource.