We describe Incilius aurarius sp. nov., a new species of toad known from several localities on the humid Caribbean slopes of the Sierra de los Cuchumatanes in Huehuetenango, Guatemala, and adjacent highlands of Chiapas, Mexico. This species previously has been confused with populations of Incilius valliceps and Incilius macrocristatus. The new species is morphologically similar to the Mexican species I. macrocristatus but differs by having less prominent crests, a distinctive golden coloration in the males, and the absence of vocal slits.