The isobaric separation of multicomponent mixtures by distillation require reliable vapour¬liquid equilibrium data. Since the experimental determination of multicomponent vapour-liqu¬id equilibrium data is laborious and time consuming, there is a need to use a predictive method for the liquid-phase activity coefficients. The abilities of Wilso and UNIQUAC equationsto predict isobaric quinary vapour-liquid equilibria using only binary constants of both equations were compared in this paper. The quinary system under study, is n. Hexane / Methylcyclopen¬tane I Cyclohexane / Benzene / Toluene. UNIQUAC equation was found to be superior in the prediction of quinary vapour-liquid equilibria with the R.M.S. Devications ranging from 0,0033- 0,0103 where as the Wilson equation could predict the quinary vapour phase with the accuracy of 0,0048-0,0104 R.M.S.D.