Isobaric vapor liquid equilibrium (VLE) data at 100kPa have been measured for the ternary system cyclohexane + cyclohexene + diethyl carbonate and two constituent binary systems: cyclohexane + diethyl carbonate and cyclohexene + diethyl carbonate. Both binary systems show moderate positive deviations from ideal behavior and do not present an azeotrope. The VLE data have been correlated by the Wilson, universal quasichemical activity coefficient (UNIQUAC), and nonrandom two-liquid (NIZTL) equations. The ternary system does not present an azeotrope and is well-estimated from binary interaction parameters. A prediction with the universal functional activity coefficient (UNIFAC)-Dortmund method has been also obtained.