Isobaric vapor-liquid equilibrium (VLE) data for the systems of methyl acetate + dimethyl sulfoxide (DIVISO), methanol DMSO and methyl acetate + methanol DMSO were determined with a modified Othmer still at 101.3 kPa. And all experimental VLE data have passed the Herington and Van Ness thermodynamic consistency tests. The experimental binary VLE data were correlated by NRTL, Wilson and UNIQUAC models and the binary interaction parameters were obtained. And the VLE data predicted by the obtained parameters agree well with the experimental data. The binary azeotrope of methyl acetate and methanol is eliminated when the mole ratio of DMSO to the binary azeotrope is approximately 1.5:1. Therefore, DMSO is a promising extractive agent for the separation of the binary azeotrope of methanol and methyl acetate in extractive distillation. (C) 2015 Elsevier B.V. All rights reserved.