Liquid-liquid equilibrium (LLE) data of the solubility curves and tie-line compositions have been determined for mixtures of (water + 2,3-butanediol + butyl acetate) at (298.15, 308.15, and 318.15) K and atmospheric pressure. Distribution coefficients and separation factors have been evaluated for the immiscibility region. The Othmer-Tobias correlation provides the coefficients of the log-log plot that is not a sensitive criterion. The LLE data of the ternary systems have been predicted by UNIFAC methods.