Kaunia R. M. King & H. Rob. is a small genus of 11 species that play an important role in Andean ecosystems, either by dominating specific vegetation units or as subdominant species at boundaries of alder communities and pino del cerro forests. The species of Kaunia are shrubs or small trees with commonly pinkish or white, usually tubular-funnelform corollas of internally smooth lobes lacking papillae, uniformly wide styles, and 20 to 26 chromosomes. A complete and exhaustive treatment of Kaunia is lacking, and so its taxonomy is herein revised. As a result of this work, together with those of previous statistical studies, 10 species of Kaunia are recognized. Kaunia ignorata (Hieron.) R. M. King & H. Rob. is placed under synonymy of K. camataquiensis (Hieron.) R. M. King & H. Rob., and a lectotype for Eupatorium hosanense B. L. Rob. is designated. Our study provides the first morphological and anatomical study of Kaunia. A key to the species, detailed descriptions, illustrations, and distribution maps for each species are also provided.