Liquid-liquid equilibrium data of toluene or benzene+n-hexane or n-heptane or n-octane hydrocarbon systems are reported with many solvent mixtures at 298.15K.Complete phase digrams were obtained by evaluating the solubility and tie line results for each ternary mixture. The thermodynamic models :NRTL,UNIQUAC,and UIFAC models were used to correlate the experimental data and to predict the phase compositions of the ternary systems.The NRTL equation fitted the experimental data better than the UNIQUAC and UNIFAC equations:the average root mean square deviations (RMSD) was 0.165 for NRTL as compared to 0.491 for UNIQUAC and 1.304 for UNIFAC.