The work aims to prepare a green packaging material with good comprehensive properties, with tea polyphenol (TP) as a modifier to modify chitosan (CS)/polyvinyl alcohol (PVA) composite films. The CS/PVA composite films with different TP mass fractions were prepared by solution blending, and the IR analysis on the composite films was done. The mechanical property, water solubility, gas barrier property and antioxidant activity were tested. The results showed that there were molecular interactions between TP and CS/PVA substrate. When the mass fraction of TP was 2%, the composite film had the best comprehensive property. The tensile strength was improved by 4.99%, and the elongation at break was at a relatively high level. Meanwhile, the water solubility, water vapor transmission rate and oxygen transmission rate of the CS/PVA composite film were decreased by 82.43%, 51.40% and 72.77%, respectively, and the antioxidant activity was increased by 58.54%. Proper addition of TP can enhance the mechanical properties and water resistance of CS/PVA composite films, and improve the gas barrier properti.