Isobaric vapor-liquid equilibrium (VLE) data at atmospheric pressure for the ternary system methanol + acetone + methyl vinyl ketone have been experimentally obtained. The measurements were conducted in a two-phase recirculation still. The experimental VLE data were correlated according to the Margules, Wilson, NRTL and UNIQUAC equations. The ternary VLE data were predicted from their constituent binaries. A comparison of model performances was made using the criterion of average absolute deviations in boiling point and in vapor-phase composition.