Abstract: Using column chromatographic and preparative HPLC technologies, we isolated a new sesquiterpene glycoside from the stem of Dendrobium nobile. With spectroscopic techniques including NMR and MS, the new compound was identified as cadalene-12-O-β-D-glucopyranoside. This type of compound was dehydrogenated from cadinane sesquiterpene to achieve a naphthalene ring, and it is rare from a natural resource.