Liquid-liquid equilibrium (LLE) data of the solubility curves and tie-line end compositions were examined for mixtures of water (1) + acetic acid (2) + diethyl succinate or diethyl glutarate or diethyl adipate (3) at 298.15 K and 101.3 +/- 0.7 kPa. The reliability of the experimental tie-line data was confirmed by using the Othmer-Tobias correlation. The LLE data of the ternary systems were predicted by UNIFAC method. Distribution coefficients and separation factors were evaluated for the immiscibility region.