The Chinese drug Pei-mu is composed of dried bulbs of Fritillaria roylei (Liliaceae) and used in Chinese medicine as antipyretic, antitussive, expectorant, etc. Previous studies revealed its components are steroidal alkaloids like Veratrum alkaloids, isolated peimine and peiminine, and presumed their structures through dehydrogenation products (e.g., 2,5-lutidine, benzofluorene derivatives). The present authors investigated the components of Bai-mo (Fritillaria Thunbergii MIQ.) produced in Japan. The plant material was sliced, dried, and processed via extraction, chloroform partitioning, and repeated chromatographies (Florisil, paper partition chromatography). Peimine was identified as the main alkaloid by its melting point (223-224°C), specific rotation ([α]D -19.4° in EtOH), and constants of its salts (HCl, HBr, MeI, etc.). A new glycoside was found, which was hydrolyzed by sulfuric acid into peimine and a sugar; the sugar was identified as β-glucose via phenylosazone formation and complete hydrolysis by β-glucosidase. This new glycoside was named peiminoside.