In this study, isothermal vapor-liquid equilibrium data were measured for the 1, 1, 1,2,3,3,3-heptafluoropropane (HFC-227ea) + isobutene system in the temperature range from (288.15 to 363.15) K at 15 K intervals. The experiments were carried out with a circulating-type apparatus with online gas chromatography. The VLE data were correlated by the Peng-Robinson equation of state with the Wong-Sandler mixing rules involving the NRTL model. The calculated results show a good agreement with the measured data, and this system presents an azeotrope at each temperature.