By using a continuous flow apparatus, quaternary solubility of acetic acid, diacetin and triacetin in supercritical carbon dioxide (scCO 2 ) have been measured at constant flow rate and temperatures of 30 ?C, 40 ?C, 60 ?C and 75 ?C in pressure range of 70-180 bar. Also binary and quaternary solubility of acetic acid is compared. Data of quaternary solubility is utilized for investigating possible extraction of each compound and selective extraction efficiencies for acetic acid by scCO 2 is calculated. Also solutions for selective extraction of triacetin and diacetin are proposed. Bartle equation is used for prediction of solubilities in further temperatures and pressures. Using the named equation the solubility of acetic acid, diacetin and triacetin in 60 ?C and pressure range of 70-180 bar is predicted and compared to experimental data. While binary solubility of acetic acid is very high, the quaternary solubility decreases in presence of diacetin and triacetin which cause more effective hydrogen bonds with acetic acid and also scCO 2 and diminish the solubility of acetic acid in the same time. Also it is observed that solubility of polar diacetin molecule in non polar solvent of CO 2 increases by increasing temperature and consequently solubility of acetic acid. It seems that acetic acid plays the role of a modifier by improving the polarity and causing increase in solubility of diacetin.