The binary solid-liquid equilibrium of Dimethyl Terephthalate (DMT), Dimethyl Isophthalate (DMI) and Dimethyl Phthalate (DMP) was investigated by experiment and differential scanning calorimetry (DSC). The result demonstrated DMT/DMI and DMT/DMP systems are eutectic while DMI/DMP is a solid-solution system. The eutectic temperature of DMT/DMI system is 336.7 K and that of DMT/DMP is 271.1 K. Furthermore, a classical solid-liquid phase equilibrium model was used to fit the experimental data of the eutectic systems of DMT/DMI and DMT/DMP and the theoretical model could describe the eutectic solid-liquid phase diagrams properly. (C) 2017 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.