A polymeric substrate is an essential component of a flexible organic electronic device. A novel composition of phenoxy and epoxy resin, phenoxy epoxy polymer (PE polymer), film is fabricated. The process of synthesis and fabrication of the film is optimized. The PE polymer film shows the high optical transmittance of 90.1%. Furthermore, the PE polymer film has exhibited high stability of transparency after humid, UV, IR, acid, and base treatments. The PE polymer film also demonstrates a higher contact angle than the PET, and considerable tensile strength and chemical resistance ability. The PE polymer film provides significant developed barrier ability to allow only 87.2% permeation than the PET film. The new PE polymer film has a high prospect for the flexible organic electronic device as a barrier film or substrate.