Isothermal vapor liquid equilibrium data for the system methanol + benzene + tetraphenylphosphonium chloride at four salt molalities {(0.100, 0.200, 0.300, and 0.500) mol.kg(-1)} have been measured with the help of headspace gas chromatography at {(308.15 and 328.15) K}. Tetraphenylphosphoniurn chloride can be used as an entrainer for the separation of methanol + benzene mixture. The experimental data were correlated using the electrolyte NRTL model.