VaporÀliquid equilibria (VLE) for 1-propanol + ethylene glycol monopropyl ether and 1-butanol + ethylene glycol monopropyl ether systems were investigated. The systems studied are isobaric VLE of the highly associating fluid mixtures, and the measurements were carried out at several pressures (60 kPa, 80 kPa, and 100 kPa) using Fischer VLE 602 equipment. A consistency test with respect to the experimental data was conducted using Fredenslud and Wisniak methods. Correlations of the experimental data were carried out using a two-term virial equation for vapor-phase fugacity coefficients and the three suffix Margules, Wilson, NRTL, and UNIQUAC models for liquid-phase activity coefficients. The results show good agreements with the experimental data at the C3E1 rich region but not at the alcohol rich region due to the strong and complex association of these systems. Additionally there are no azeotrope points.