Natatolana Bruce, 1981 is one of the most speciose, widespread and abundant isopod genera occurring in marine environments. Species in the genus are ecologically important as scavengers and occasionally have a negative impact on commercial fisheries by feeding on catches restrained in traps, nets or on lines. The study of Natatolana species is hampered by difficulties in identification, inadequate descriptions and a lack of overall taxonomic revision. In this study, taxonomic, biogeographical and ecological information is reviewed for all 72 species of Natatolana now recognized worldwide. A revised generic diagnosis, a key to species, and diagnoses and synonymies for all species are presented. Phylogenetic relationships of the genus and species are discussed. Thirteen new species are described, 10 from Australia: N. brucei n.sp., N. buzwilsoni n.sp., N. debrae n.sp., N. femina n.sp., N. flexura n.sp., N. helenae n.sp., N. lilliput n.sp., N. rusteni n.sp., N. sinuosa n.sp., and N. zebra n.sp., and three from New Zealand: N. aotearoa n.sp., N. honu n.sp., and N. paranarica n.sp. Redescriptions or new illustrations are provided for an additional seven species. Lectotypes are designated for three species. Justification for placement of N. lurur and N. wullunya as junior synonyms of N. arcicauda and N. nammuldi, respectively, is presented.