Abstract: 'Xia-ye-gui' is a valuable plant of Cinnamomum recently discovered in China. The main constituent of its leaf essential oil is safrole whose content is up to 97%~ 99%. As an impor-tant source of safrole, its exploitation and utilization are in prospect. But its botanical name is confusing now. It is regarded sometimes as a variety or even a form of Cinnamomum burmannii (C. G. & Th. Nees) Bl. We prefer to regard it as a distinct species based on its morphology, habitat, phenology and chemical constituents in comparision with those of C.burmannii. 'Xia-ye-gui' is evidently an ancient riparian relic closely related to C.burmannii, but its botanical name is C. heyneanum Nees.

Key words: 'Xia-ye-gui'