Abstract: Vapor permeation has potential applications in the separation of organic solvent-water mixtures.Adsorption property of organic vapor influences mainly the membrane selectivity in vapor permeation.The adsorption isotherms of water,acetone, methanol, ethanol and isopropanol vapors on γ-Al₂O₃ membrane were measured by methods of dynamic chromatography.The parameters of the relevant Pickett isotherms were calculated.