Abstract: The extract oil is a kind of by-product coming from lubricating oil solvent refining process. The processing and utilization of extract oil was limited and used as blending component of fuel oil because of high content of aromatic, small amount of saturated alkane, colloid and asphaltene. Therefore, the economic benefit is low. In order to improve the utilization value of extract oil, it can be further processed and used after treatment, including blending extract oil into feedstock of refinery units, blending paving asphalts, preparing surfactant, producing rubber filling oil, solvent oil, heating oil, insulating oil and condensed polynuclear aromatic resin. The comprehensive utilization prospect of extract oil was prospected.