The solubility of disodium 5'-guanylate heptahydrate (5'-GMPNa2) in water-ethanol binary solvent mixtures was measured at temperatures ranging from 278.15 K to 323.15 K using a dynamic method. The solubility data were correlated by the Apelblat equation, the Combined Nearly Ideal Binary Solvent/Redlich-Kister (CNIBS/R-K) equation and the modified Jouyban-Acree equation, respectively. Results showed that a reasonable match with experimental data is obtained from the Apelblat equation and CNIBS/R-K equation, while the modified Jouyban-Acree equation contains parameters including both solvent composition and temperature. The thermodynamic functions Gibbs free energy, enthalpy and entropy of solution were also calculated based on solubility data of 5'-GMPNa2 determined in binary water + ethanol solvent mixtures by using van't Hoff equation. The dissolving process is endothermic and the dissolution driving force converts from enthalpy-driving to entropy-driving. (C) 2014 Elsevier B.V. All rights reserved.