On the basis of recent fieldwork, six new species of Cyathea from northern Peru are described: Cyathea carolinae, C. cisandina, C. grata, C. oscarorum, C. phoenix, and C. novoi. All were found on sandstone subtrates under different precipitation regimes. Here, we illustrate these species, discuss their natural history, compare them to their putative close relatives, and discuss the implications of their discovery for the floristics of South American tree ferns.