Lignin, a natural polymer abundant in plant cell walls, has garnered attention for its potential as a sustainable and renewable material in various applications. This chapter explores the utilization of lignin in the development of hydrogels, highlighting its unique properties and sources. The formation mechanisms and characteristics are discussed, along with techniques for modifying lignin to enhance its compatibility and performance in hydrogel applications. Furthermore, the diverse range of applications, including in biomedical, environmental, and industrial fields, are examined. Challenges associated with the synthesis and scalability of these hydrogels are addressed, and future directions for research and development in this promising area are outlined. Overall, this chapter provides insights into the potential of lignin-based hydrogels as eco-friendly materials.