For a long time, lignin was considered a waste product of the pulp and paper industry. However, as industries shift toward sustainability, materials once treated as waste are now seen as valuable byproducts with potential for creating innovative materials. Thanks to its complex chemical structure and its more hydrophobic nature compared to other bio-based polymers, lignin has become the focus of numerous studies, attracting attention from various market segments, including the food packaging sector. Currently, the food packaging sector is a major contributor to plastic waste, posing a serious environmental challenge. Among the alternatives explored to address this issue, packaging made from bio-based polymers has gained attention. However, despite being more environmentally friendly, these materials face significant performance limitations compared to conventional plastics. In this context, lignin stands out as a promising additive for packaging, thanks to its natural origin, biodegradability, and its potential to enhance the mechanical, thermal, and barrier properties of bio-based polymers. In addition, lignin can increase the hydrophobicity of polymer matrices while imparting antioxidant and antimicrobial properties. This chapter explores the incorporation of lignin into various polymer matrices for the development of food packaging. The results from numerous studies are discussed, along with the limitations, challenges, and future perspectives surrounding this complex molecule. Once discarded by industry, lignin now holds significant scientific importance and added value.