Isobaric vapor-liquid equilibrium(VLE) data for the quaternary system methyl acetate + methanol + isopropanol + isopropyl acetate and the constituent binary system methyl acetate + isopropyl acetate have been determined at 101.3 kPa with a modified Rose still. The rest of binary systems VLE data were obtained from the literature. The measured experimental data were found to be thermodynamically consistent according to the Herington analysis. Experimental binary data have been correlated by Wilson, NRTL and UNIQUAC activity coefficient models. The three models with their best-fitted parameters were used to predict the quaternary vapor-liquid equilibrium. A comparison of performances was made by using the criterion of average absolute deviations in boiling point and in vapor-phase composition. The results showed that the NRTL model yielded a good prediction for the quaternary system from the parameters of the correlated binary systems. (C) 2013 Elsevier B.V. All rights reserved.