We describe and illustrate four new species of dragon's blood trees (Croton sect. Cyclostigma) from western South America. Three of the species, Croton beckii from Bolivia and Peru, C. camposii fromPeru, and C. santamartensis fromColombia, grow inmontane Andean forest,whereas C. tumbesinus occurs in dry forest of the Tumbes/Piura ecoregion of western Ecuador and Peru. The characters that place them in Croton sect. Cyclostigma include the arborescent habit, the presence of reddish to yellowish latex, an indument of stellate trichomes, conspicuous and persistent stipules, acropetiolar/basilaminar nectary glands, and terminal inflorescences with bisexual cymules at the base. These new species give additional support for the Andean region being the main center of diversity of this Neotropical Croton clade, as well as being a region whose biodiversity knowledge is still incomplete. © 2018 by the American Society of Plant Taxonomists.