A revision of the genus Stomatanthes (Asteraceae, Eupatorieae) is presented. A cladistic analysis of 43 qualitative and eight quantitative morphological characters resulted in one tree that suggests a narrower delimitation of the genus relative to previous circumscriptions. Stomatanthes thus comprises three species, one widespread in sub-Saharan Africa and the other two endemic to restricted areas in central Africa. A cluster analysis and a non-metric multidimensional scaling were also performed. Of the 25 quantitative traits originally measured for the analysis, eight (blade length and width, involucre length, corolla length, corolla limb width, corolla tube width, thecae length, anther apical appendage length) provided clustering information and indicated the same groupings as the cladistic analysis. This revision also includes full descriptions of species, photographs, illustrations, and distribution maps.