Solubilities of 2-ethyl-1-hexanol (1), 2-ethyl hexanoic acid (2), and their mixtures in supercritical carbon dioxide (SC-CO2) (3) were reported. Solubilities were measured at a constant temperature of 313 K and 323 K, at pressures varying from (68 to 180) bar for the binary systems and at a constant pressure of 138 bar at temperatures varying from (313 to 373) K for the ternary system. Temperature dependences of the solubilities for a x(1) = 0.5 mixture were determined. The effect of the mixture composition of the acid + alcohol mixture in SC-CO2 was studied. The total solubility of the mixtures in SC-CO2 is independent of the x, of the liquid mixture in the equilibrium cell. The Chrastil model for solubilities at 313 K and 323 K was evaluated.