Abstract: The main components in the 100~220 ℃ fraction of direct coal liquefaction oils are phenolic compounds, aromatic hydrocarbons and aliphatic hydrocarbons. And their mass content percentages are 35.50%, 35.25%, and 28.17% respectively. In order to decrease the hydrogen consumption in the downstream processing, the best choice is to extract the phenolic compounds firstly. The authors employed the COSMO-RS model to screen the deep eutectic solvents (DESs) for phenol-aromatic hydrocarbon system, and applied the σ-profile and σ-potential to study the interactions of DESs with the phenols, aromatics, and aliphatic hydrocarbons to be separated during the extraction process; with the help of Infrared spectroscopy and Ultraviolet-visible spectroscopy, the mechanism of phenol extraction by DESs was revealed; 3 kinds of screened DESs: Choline Chloride (ChCl):Ethylene Glycol (EG) (1:1.5), Betaine (Bet):EG (1:2.5), and Tetraethylammonium Bromide (TEAB):EG (1:3) were used for the separation of m-cresol-isopropylbenzene in order to optimize the extraction process conditions for the extraction of phenolic compounds in the 100~220 ℃ fraction section of direct coal liquefaction oils, and to investigate the recycling p