Type 2 diabetes mellitus (T2DM) is a global health challenge with limited efficacy of current treatments, necessitating alternative therapies. Plant-derived pectin, composed of galacturonic acid and structural domains such as homogalacturonan, has shown promise as an anti-diabetic agent. Pectin exerts its therapeutic effects through multiple mechanisms, including enhancing β-cell function, regulating glucose metabolism, improving insulin sensitivity, inhibiting digestive enzymes, and restoring gut microbiota balance. Its bioactivity is influenced by physicochemical properties like molecular weight, degree of methylation, and structural complexity. This review explores the anti-diabetic potential of pectin, its structure-activity relationships, and mechanisms of action, providing insights for its development as a novel therapeutic agent in T2DM management.