A revision of the genus Phaeanthus Hook.f. & Thomson (Annonaceae) is presented. The genus comprises 8 species. A key to the fruiting and/or flowering specimens of the genus is included. The genus consists of shrubs to small-sized trees from Malesia and Vietnam. It is characterised by sepals and outer petals that are alike, numerous carpels and stamens, the latter truncate with a distinctive connective prolongation, monocarpous fruits, and leaves often drying dark brown to black. A phylogenetic analysis shows the monophyly of the genus and that Phaeanthus nutans can be considered the sister species of the remaining species.