Bioadhesive hydrogels play a crucial role in biomedical applications due to their capacity to adhere to biological surfaces. This study investigates a novel bioadhesive hydrogel system developed from poly(vinyl alcohol) (PVA) and ascorbic acid (AS), cross-linked through gamma irradiation at 7 kGy, and modified with 5 wt % tannic acid (TA). The primary objective was to enhance the hydrogel's bioadhesive, mechanical, and antimicrobial properties. Mechanical testing revealed that the (PVA/AS)/TA hydrogel exhibited significant improvements, with a lap shear strength of 92 kPa, a tensile strength of 0.57 MPa, and an elongation at break of 180%, compared to the unmodified variant. Antimicrobial efficacy was assessed against bacterial strains, including and , showing potent inhibitory effects with minimum inhibitory concentration (MIC) values of 25 μg/mL and 30 μg/mL, respectively. The findings indicate that the (PVA/AS)/TA hydrogel is a promising candidate for wound healing, drug delivery, and tissue engineering applications. It showcases its novelty in improving bioadhesive properties while providing antimicrobial functionality, thus addressing critical challenges in biomedical material design.