Anoectochilus roxburghii polysaccharide (ARP) is a kind of bioactive substance, consisting of monosaccharides polymerized by glycoside bonds. It is extracted from Anoectochilus roxburghii and has effective functions to decrease blood sugar and blood fat, and to protect liver and kidney. It also has excellent effects on sleep promotion, anti-tumor, and immunity enhancement. Based on the research of ARP in recent years, this article reviewes the extraction methods of ARP and mechanism of its biological activity, briefly analyzes the characteristic of its structure, and summarizes the differences in the content of different sources of ARP and the application of ARP in foods.