Lignin, a heterogeneous biopolymer derived from plant cell walls, is one of earth’s most abundant natural polymers after cellulose, offering immense potential for bio-based materials, chemicals, and energy applications. Recent advancements have underscored the importance of characterizing lignin’s diverse structural features and functional properties to unlock its full potential. Chromatography-based techniques are particularly effective for lignin separation, quantification, and structural elucidation. This chapter highlights commonly used chromatographic methods for lignin analysis, detailing their principles, advantages, limitations, sample preparation strategies, detector choices, and optimized chromatographic conditions. By providing a comprehensive overview of these techniques, the chapter equips researchers with valuable insights to select appropriate methods for lignin characterization, ultimately enhancing our understanding of lignin’s structure-property relationships and enabling its efficient valorization for diverse applications. These advancements contribute to the broader effort of developing sustainable solutions for renewable resource utilization.