Films of poly(vinyl alcohol)/wheat gluten (PVA/WG) polymer blends at different compositions were prepared by solution casting and then exposed to a constant dose of gamma irradiation. In addition, the PVA/WG polymer blends were modified by adding a constant ratio (4%) of tannic acid (TA) to the casting solution. The PVA/WG polymer blends before and after gamma irradiation as well as those modified by tannic acid were characterized by Fourier transform infrared (FTIR) spectroscopic analysis, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and measuring the tensile mechanical properties. The antimicrobial activity of PVA/WG polymer blends was also investigated. FTIR spectroscopic analysis indicated that a hydrogen bond was formed between TA and PVA also irradiation improves the adhesion between PVA and WG this conclusion also supported by scanning electron microscopy (SEM) and measuring the tensile mechanical properties. The antimicrobial properties indicated that irradiated sample was better than unirradiated samples.