Liquidliquid equilibria data for the ternary system methyl isobutyl ketone + m-benzenediol + water were measured at temperatures of (298.15, 308.15, and 318.15) K and atmosphere pressure. The reliability of the experimental tie-line data was verified by the Hand and Bachman equations. The experimental data were correlated with the nonrandom two-liquid (NRTL) and universal quasichemical (UNIQUAC) models. The binary interaction parameters of these two models were reported. Both models correlated the experimental data successfully.