Abstract:From Hypodematium sinense lwatsuki (Thelypteridaceae) a new xanthone C-glycoside was isolated. According to chemical properties and spectroscopic (IR, UV, MS, 1H-and 13C-NMR) analysis, the structure was established as 1,3,6-trihydroxyxanthone-8-C-β-D-glucopyranoside, named chongzujueside.