Pectin, an acidic polysaccharide, is naturally present primarily in the cell walls and inner layers of higher plants. Pectin is extensively used in food, pharmaceutical, cosmetic, and other industries owing to its exceptional attributes encompassing superior gelation, emulsification, antioxidant activity, stability, biocompatibility, and nontoxicity. Due to the increasing demand for pectin, there is a short supply in the domestic pectin market. Currently, the domestic production of pectin is heavily reliant on imports, thus emphasizing the urgent need to enhance its local manufacturing capabilities. Due to the diverse sources of pectin and variations in extraction and purification methods, its content, physicochemical properties, and biological activity are influenced, consequently impacting the market application of pectin. Therefore, this paper comprehensively reviews the extraction and purification process of pectin, in vivo metabolism, and biological activities (including antitumor, immunomodulatory, anti-inflammatory, antioxidant, hypoglycemic and hypolipidemic effects, antimicrobial properties, accelerated wound healing potential, promotion of gastrointestinal peristalsis, and alleviation of constipation as well as cholesterol-lowering effect). Furthermore, it explores the diverse applications of pectin in food science, biomedicine, and other interdisciplinary fields. This review serves as a valuable resource for enhancing the efficiency of pectin content improvement and exploring the potential value and application of pectin in a more scholarly and scientifically rigorous manner.