Abstract: A new experimental apparatus for the measurement of vapor liquid equil ibrium of polymer solution by Quartz Crystal Microbalance (QCM) method was established. It is sensitive in the measurement of solvent weight absorbed by polymer, and it will take shorter time to approaches the equilibrium. The vapor liquid equilibrium data for the systems of toluene/polystyrene benzene/polystyrene and cyclohexane/polystyrene at 303.15K and 313.15K have been determined by using this apparatus. A good agreement between experimental data in this work and literature values is obtained.