Isothermal vapor-liquid equilibria (VLE) for mixtures containing 1,1,1-trichloroethane + tetrahydrofuran + propan-2-ol have been measured using a modified version of a Boublik-Benson still at 298.15 K. A test of thermodynamic consistency, like McDermott-Ellis method was applied to the activity coefficients. Excess molar Gibbs free energies were calculated over the entire range composition. Different expressions existing in the literature were used to predict the activity coefficients.