Most studies of bryophytes in Brazil have focused on the Atlantic and Amazon forests, leaving the Caatinga as the biome least bryologically studied in the country. A bryofloristic survey of Serra da Capivara National Park was undertaken to analyze species richness, the distribution of species among Brazilian biomes, and the geographic distribution of species. A total of 450 samples of 62 species were collected, representing 48 mosses, 13 hepatics, and one hornwort. The resulting species list includes 22 new records for the Caatinga, 34 new records for the state of Piaui, and two for the Northeast Region of Brazil. About 60% (37 spp.) of the species have broad distributions in Brazil while 13 have moderate distributions and 12 are considered restricted. The results reinforce the importance of floristic inventories in Brazil and the maintenance of Parque Nacional da Serra da Capivara as an area for the conservation of bryophytes. Keywords Caatinga, liverworts, mosses.