Abstract: The solubilities of styrene in supercritical carbon dioxide under different supercritical conditions are determined.The range of temperature covered is 323.15-33.15K and pressure 3.0-24.0MPa.A model representing solubility behavior is derived from the solvation concept, the equilibrium constant of high-pressure reaction and the rules of phase equilibrium. It is tested by experimental results with good agreement. Also, some experimental results from the literature are reproduced by means of this model.