Equilibrium studies on the extraction of thiophene from its mixtures with methylcyclohexane using two imidazoliumionic liquids have been carried out. LLE data were obtained for mixtures of 1-methyl-3-octylimidazolium bis[trifluoromethylsulfonyl]imide or l-methyl-3-octylimidazolium tetrafluoroborate with thiophene and methylcyclohexane at atmospheric pressure and 298.15 K. Tie-line compositions were correlated using the NRTL equation,but considerable deviations from experimental data were found at high concentrations of thiophene. Distributioncoefficients and selectivities were evaluated.