Inspired by natural organisms, biomimetic materials with exceptional biocompatibility, degradability, and multifunctionality have emerged as promising candidates for biomedical applications. Lignin, a plant-derived organic polymer, has gained attention due to its intrinsic antioxidant activity, adhesive properties, and biocompatibility. Despite its structural advantages, challenges in stability, biodegradability, and practical implementation hinder its utilization. Structural modifications through chemical/physical treatments or microbial/enzymatic can optimize lignin's bioactivity, mechanical strength, and adhesion, enabling applications in drug delivery, Ultraviolet (UV) shielding, sensing, and wound healing. This review outlines lignin sources, modification principles, and adhesion of biomaterials mechanisms, while showcasing innovative lignin-based materials in biomedical contexts. We highlight their roles in therapeutic delivery systems, tissue engineering & regenerative medicine, and functional biomedical devices, emphasizing lignin's low toxicity and environmental adaptability. By addressing current limitations in processing techniques and clinical translation, we discuss lignin's potential to bridge laboratory research and practical medical solutions. The analysis concludes with an evaluation of lignin's untapped value in sustainable biomedicine, proposing strategies to overcome scalability and standardization barriers. This synthesis provides critical insights for advancing lignin-based technologies toward clinical implementation while maintaining ecological sustainability.