This research focuses on measuring the solubility of three antioxidants-ethylenediaminetetraacetic acid disodium salt hydrate, ethylenediaminetetraacetic acid calcium disodium salt hydrate, and L-cysteine hydrochloride-in supercritical carbon dioxide. Using a semiflow apparatus, the experiment takes data at 308.15, 313.15, and 318.15 K with pressure ranging from 10 to 22 MPa (for ethylenediaminetetraacetic acid disodium salt dihydrate) or from 12 to 24 MPa (for ethylenediaminetetraacetic acid calcium disodium salt hydrate and L-cysteine hydrochloride). Two semiempirical equations-one proposed by Chrastil, the other Mendez-Santiago and Teja-are applied to find the correlated relationship of the experimental data. With the choice of fitted parameters, the correlation derived from the two equations are satisfactory: the average absolute relative deviation is under 5.1%.