This review article provides a comprehensive overview of *Ganoderma lucidum* polysaccharide (GLP), a bioactive substance derived from the edible fungus *Ganoderma lucidum*. GLP is known for its various health benefits, including anti-tumor, anti-oxidation, and anti-cancer properties. The paper discusses the extraction and purification methods of GLP, emphasizing the importance of effective cell wall disruption and impurity removal. It also explores the relationship between GLP structure and biological activity, highlighting the significance of primary, secondary, tertiary, and quaternary structures. The review covers both qualitative and quantitative analysis methods, including traditional techniques like the phenol-sulfuric acid method and modern approaches such as hyperspectral imaging and machine learning. Additionally, the article addresses the challenges and future directions in GLP research, such as improving extraction efficiency, characterizing advanced structures, and expanding applications in food and healthcare products. The authors propose several suggestions for future studies, including chemical modification, nano delivery systems, and the establishment of a shared database to enhance the understanding and utilization of GLP.This review article provides a comprehensive overview of *Ganoderma lucidum* polysaccharide (GLP), a bioactive substance derived from the edible fungus *Ganoderma lucidum*. GLP is known for its various health benefits, including anti-tumor, anti-oxidation, and anti-cancer properties. The paper discusses the extraction and purification methods of GLP, emphasizing the importance of effective cell wall disruption and impurity removal. It also explores the relationship between GLP structure and biological activity, highlighting the significance of primary, secondary, tertiary, and quaternary structures. The review covers both qualitative and quantitative analysis methods, including traditional techniques like the phenol-sulfuric acid method and modern approaches such as hyperspectral imaging and machine learning. Additionally, the article addresses the challenges and future directions in GLP research, such as improving extraction efficiency, characterizing advanced structures, and expanding applications in food and healthcare products. The authors propose several suggestions for future studies, including chemical modification, nano delivery systems, and the establishment of a shared database to enhance the understanding and utilization of GLP.