This research explores the intersection between the history of medicine and that of the body by tracing the medicalization of a unique plant: Ginkgo biloba. As the only surviving species of its kind, ginkgo has become one of the most popular herbs in modern times. Different from current understandings of ginkgo’s medical history, my essay identifies great divergences that have surfaced in different societies’ contemplations of ginkgo as a pharmaceutical. For example, when the Chinese in the seventeenth century proved that ginkgo could cure disorders of the lungs, their counterparts in Edo Japan (1603‐1868) were convinced that ginkgo was effective in promoting digestion. Also, when ginkgo was widespread in Europe in the late twentieth century, Europeans came to formulate that ginkgo supported mental sharpness. This essay interprets such divergences by applying what anthropologists call “regional biologies.” The ways in which different societies conceptualize ginkgo as part of their living worlds, for example, agriculture, horticulture, taxonomy, and evolutionary theory, help shape ginkgo’s medicalization and, in turn, how the body perceives of an object’s efficacies.