Abstract: Purifying eicosapentaenoic acid (EPA) from fish oil with supercritical CO₂ was carried out, using a laboratory apparatus characterized by a rectification column of 9.7 mm internal diameter and 1.1 m effective height. To improve the supercritical fluid liquid contact, a scourer rotor was used in the extraction cell, and the column was packed with Dixon ring. Also, to level up the separation ability, the extraction pressure was increased step by step, and the column temperature was kept in linear gradient from bottom 35 ℃ to top 80 ℃.