The state of Rio Grande do Norte is considered a data gap for bat species records in Brazil. The state is also currently target of large economic projects with potential impacts on bats, especially wind farms and mining enterprises. In addition, Rio Grande do Norte has few conservation units in which there is no systematic study on bat fauna. The Nísia Floresta National Forest (NFNF), a federally protected area of 174 hectares, is located in the eastern coast of Rio Grande do Norte and corresponds to one of the last remnants of Atlantic Forest in the state, in its northernmost limits. A bat inventory was conducted in NFNF using mist nets set at ground level, from sunset to sunrise, from December 2011 to December 2012, totaling 25 sampling nights. We captured 1,379 bats belonging to four families and 16 species. Artibeus planirostris (Phyllostomidae) was the most frequently captured species (n = 685; 50%), followed by Myotis lavali (Vespertilionidae) (n = 248; 18%) and Phyllostomus discolor (Phyllostomidae) (n = 147; 11%). Peropteryx leucoptera, Phyllostomus discolor, Phyllostomus hastatus, Lophostoma brasiliense, Lasiurus blossevillii, Myotis lavali, and Promops nasutus are new records for Rio Grande do Norte, increasing the current number of bat species from 25 to 32 in this state. Further inventories, especially using acoustic surveys with bat detectors, might add more species to the NFNF bat list.