Twenty one new species are added to the leafhopper genus Erythrogonia from South America. Sixteen species, acuminata, ancora, anisa, apicalis, bidigitata, bispinata, clavata, elongata, expanda, gorgonica, grandis, lateralis, lobata, retosa, rotunda, and undulata, from Colombia; two species, guianae and rara, from French Guiana; two species, boliviana and dirhachis, from Bolivia; and one species, peruviana, from Peru. A list of species with new country records, and a key to the species of this genus is also included.