In this study, the vapor pressures of benzyltributylammonium chloride and ethanol solutions were measured from 298.25 K to 318.15 K, and the enthalpies of vaporization of this mixture were estimated by the Clausius-Clapeyron equation. The vapor-liquid equilibria of the ethanol and water mixtures with 2 m and saturated concentrations of the same organic salt were measured with an Othmer type equilibrium cell under atmospheric pressure. The uncertainty of the calibration is +/-0.0019 mole fraction for the water + ethanol mixture and that of temperature is 0.1 K.