By use of a laser monitoring observation technique, the solubilities of DL-p-hydroxyphenylglycine (DL-p-HPG) sulfate in binary acetone + water solvent mixtures were determined by the synthetic method from 303.15 K to 323.00 K, respectively. Results of these measurements were correlated by the combined nearly ideal binary solvent (CNIBS)/Redlich-Kister equation. For the five group data studied, the combined ideal binary solvent (CNIBS)/Redlich-Kister equation was found to provide an accurate mathematical representation of the experimental data.