The solubilities of pure 5-sulfosalicylic acid and its equal-molar mixture with p-aminobenzoic acid in supercritical carbon dioxide were measured at (308 to 328) K and over the pressure range from (8.0 to 21.0) MPa. The effect of temperatures and pressures on the solubility was investigated, and the interaction of the mixed solutes was also studied in this work. The binary and ternary solubility data of 5-sulfosalicylic acid and p-aminobenzoic acid were correlated by the Chrastil equation with satisfactory agreement.