Solubilities of four thioxanthone derivatives in supercritical CO2 have been measured at the temperatures (308, 318, 328, 338, and 348) K in a pressure range from (122 to 355) bar. The measurements have been performed by using a simple static-sampling type apparatus. The effects of temperature, pressure, and density of carbon dioxide on solubility of thioxanthone derivatives have been investigated. The measured solubilities were correlated using a semiempirical model. The calculated results show satisfactory agreement with the experimental data.