The invention provides a high-barrier flexible back film. The high-barrier flexible back film mainly comprises a substrate film, 
aluminum foil, an uvioresistant 
coating, a protection film layer, and an 
adhesive layer; two sides of the 
aluminum foil are compounded with the substrate film through an 
adhesive respectively; the uvioresistant 
coating can be directly coated or sputtered outside a compound film; the protection film layer can be directly coated or compounded on the uvioresistant 
coating; and the 
adhesive layer is coated on the inner side of the compound film, so the high-barrier flexible back film can be obtained. In the high-barrier flexible back film, the 
aluminum foil is used as an intermediate layer and has an extremely high barrier property, so the high barrier requirement of novel flexible thin-film solar products such as Cu(InGa)Se2 (CIGS), OPV and the like can be met, and the aluminum foil can reflect light to improve the conversion efficiency of 
solar energy; moreover, the high-barrier flexible back film is mainly prepared by a compound process. The obtained 
solar cell back film has the extremely high barrier property and 
mechanical strength, and can protect a 
solar cell well; and the compound process is mainly adopted, a production process is simple, production technologies for all the materials are mature, and all the materials are low in cost. Therefore, the back film is high in scale yield, the cost of the back film is far lower than that of similar products on market, and due to the 
advantage of the flexibility of the back film, the characteristics of flexibility, thinness and the like of a 
thin film solar cell can be exerted well.