Gentiana is a genus of flowering plants belonging to the gentian family (Gentianaceae), the tribe Gentianeae, and the monophyletic subtribe Gentianinae. With about 400 species, it is considered a large genus. Gentians are notable for their mostly large trumpet-shaped flowers, which are often of an intense blue hue.

Gentianaceae is a family of flowering plants of 103 genera and about 1600 species.