Eleven species of reptiles are reported from Nauru in the first systematic treatment of the herpetofauna. Four of the species are marine; the seven others include six lizards (four geckos, two skinks) and one snake. Gehyra mutilata (Wiegman), G. oceanica (Lesson), Pelamis platura (Linnaeus), and Ramphotyphlops braminus (Daudin) are recorded on Nauru for the first time. With the exception of Emoia arnoensis Brown & Marshall, which is endemic to eastern Micronesia, the herpetofauna consists of species that range widely among the west-central Pacific Ocean islands. The only known record of E. arnoensis from Chuuk possibly is based on a misassigned locality, in which case the range of the species would be limited to the Marshall Islands, Nauru, and Kosrae. There is no evidence to suggest that habitat modification on Nauru stemming largely from more than a century of phosphate mining has reduced the number of reptile species.