In this work, we investigated the thermodynamic properties of flame retardant bisphenol A-bis (5,5-dimethyl-1, 3-dioxaphosphorinanyl-2-oxy phosphate ester) (BADOPE), including the melting point and the enthalpy of fusion of BADOPE by differential scanning calorimeter (DSC) and the thermal stability of BADOPE by thermogravimetric analysis (TGA). BADOPE was synthesized and characterized by EA, FT-IR and 1HNMR. Using a static analytic method, solid−liquid phase equilibrium data (the solubility) of BADOPE in acetonitrile, acetone, methanol, tetrahydrofuran, ethanol, ethyl acetate, methylethylketone and 1,4-dioxane were obtained at temperatures ranging from 293 to 338 K. Several thermodynamic models, including the ideal, modified Apelblat, Wilson, NRTL, UNIQUAC and Scatchard-Hildebrand models, were applied to correlate the experimental solubility data.