The solubilities of mercaptosuccinic acid in binary solvent mixtures consisting of water + methanol; water + ethanol; and water + acetone were determined by a dynamic method over the temperature from 278.15 to 333.15 K. The solubility data were correlated with the modified Apelblat equation and the semi-empirical Buchowski-Ksiazczak lambda h equation. The Buchowski-Ksiazczak lambda h equation can regress the solubility data much better than Apelblat equation. The calculated values are in good agreement with the experimental values. This study provides valuable data for the mercaptosuccinic acid purification by the preferential crystallization procedure. (C) 2013 Elsevier B.V. All rights reserved.