The ability to predict the solubility of solids in supercritical fluids is important in many applications, including the food and pharmaceutical industries, chemical processing, and separations. In the present work, the solubility of cholesterol and its esters in supercritical carbon dioxide are investigated by applying equations of state. The equations of state used are: (a) the modified Peng-Robinson equation of state (Gasem et al.), and (b) the modified Peng-Robinson equation of state (Boston and Mathias). These equations of state have an exponential alpha function and it is found that they give better results than those resulting from the Peng-Robinson equation of state which has a linear alpha function. The interaction parameters are also obtained for the systems studied and the percentage of average absolute relative deviation (%AARD) is displayed for each calculation.