Experimental liquid-liquid equilibrium data were measured for benzene + cyclohexane + 1-butyl-3-methylimidazolium hexafluorophosphate ([C(4)mim]PF(6)) at atmospheric pressure and (298.2, 308.2, and 318.2) K. The selectivity of [C(4)mim]PF(6) for benzene is in the range of (20 to 60) when the mass fraction of benzene in the cyclohexane-rich phase is less than 0.08, which increases with a decrease in benzene content. The selectivity is also dependent oil the temperature. The highest selectivity is obtained at 308.2 K in this work. Considering the high selectivity for benzene and the negligible Solubility in benzene + cyclohexane Mixtures, [C(4)mim]PF(6) may be used as a potential extracting solvent for the separation of benzene and cyclohexane.