The Southeast Asian genus Rhinacosmus Kraatz is diagnosed and discussed, the species are keyed, a checklist of the species is given, and the Leiden collection is recorded. Four species are recognized, including R. javanus sp. nov. (West Java). For R. pilosus (Mohnike) and inermis (Janson) lectotypes are designated; the former name appears to be a senior synonym of R. knirschi Schürhoff.