Twenty species of reptiles are recorded from the Mortlock Islands, Chuuk, Federated States of Micronesia. The eight geckos and eight skinks together comprise 80% of the herpetofauna; amphibians are absent. Most of the species are widespread in the west-central Pacific, but the recently described gecko Lepidodactylus oligoporus is known only from the type locality on Namoluk Atoll. Hemidactylus frenatus appears to be displacing Gehyra mutilata, which is common only on Namoluk Atoll, where H. frenatus is unrecorded. Five species of skinks of the genus Emoia are sympatric on Satawan Atoll. Partial habitat segregation was observed in three morphologically very similar species of Emoia, with E. cyanura being more frequently encountered in beach strand and other open, sun-exposed areas; E. caeruleocauda in shady forest; and E. impar in sundappled forest patches.