The Costaceae are represented in Peru by three genera and 26 species (Brako & Zarucchi, 1993), all herbaceous plants. One genus, Monocostus, is endemic to Peru. Here we recognize three endemic species in two genera. The endemic species are found in Humid Amazonian Forests and Premontane Forests between 300 and 800 m elevation. None of the species have been reported to date from Peru's protected areas network.