Abstract: Houttuynia cordata Thunb was commonly known as "antibiotic of traditional Chinese medicine", which is an important medicinal/dietary resource in China. Houttuynia cordata polysaccharide (HCP) is one of its main active components, and many researches have shown that HCP can exert potent antibacterial, antiviral, anti-inflammatory, immune regulation, intestinal protection, antioxidant, and other bioactivities. Recently, its structural characteristics and biological activity have become the focus of researchers. In this work, the extraction methods, structural characteristics, bioactivity, and structure-activity relationship of HCP are highlighted. Taken together, the article is not only beneficial to promote the application and development of Houttuynia cordata Thunb and polysaccharide resources, but also provides reference for further investigation involved in the structure-activity relationship of HCP.