Solid-liquid equilibrium data for six organic binary mixtures of heptanedioic acid (1) + pentanedioic acid (2) (eutectic temperature T-E = 341.9 K, eutectic composition x(1E) = 0.391), hexanedioic acid (I) + heptanedioic acid (2) (T-E = 365.4 K, x(1E) = 0.239), heptanedioic acid (1) + 2,3-dimethylbutanedioic acid (2) (T-E = 348.9 K, x(1E) = 0.443), heptanedioic acid (1) + 2,2-dimethylbutanedioic acid (2) (T-E = 358.8 K, x(1E) = 0.667), heptanedioic acid (1) + 3-methylpenetandioic acid (2) (T-E = 338.8 K, x(1E) = 0.357), and 2,2-dimethylbutanedioic acid (1) + 3-methylpenetandioic acid (2) (T-E = 348.3 K, x(1E) = 0.212) were measured in this study using differential scanning calorimetry (DSC). All six systems show simple eutectic behavior. The experimental data were correlated using the Wilson and nonrandom two-liquid (NRTL) activity coefficient models, and satisfactory results are presented.