Vapor-liquid equilibria are important as the base of equipment design such as distillation and evaporation. Extensive vapor-liquid equilibrium data have been reported to date. Distillation processes under elevated pressures (100 to 1,000 kPa) for polar-components systems attract attentions recently and the related vapor-liquid data are becoming more important. However, such data for non-hydrocarbon systems are not sufficient. This article deals with the measurement of bubble point using an ebulliometer operated at elevated pressures. Firstly the bubble point for benzene + cyclohexane system have been measured at 10 to 400 kPa. The vapor-liquid equilibria have been determined using two methods, i.e. Mixon method and NRTL equation. Finally, a comparison between the calculated azeotrope for benzene + cyclohexane system and reported data was done to confirm the validity of estimation results.