The damselfish genus Dascyllus (family Pomacentridae) is reviewed. The group contains the following nine species which are primarily inhabitants of tropical reefs: albisella (Hawaiian Islands), aruanus (widespread Indo-Pacific), carneus (Indian Ocean), marginatus (Red Sea), melanurus (Indo-Australian Archipelago), reticulatus (E. Indian Ocean and W. Pacific), strasburgi (Marquesas Islands), trimaculatus (widespread Indo-Pacific), and flavicaudus n.sp. (southeastern Oceania) which is described in detail and compared with its nearest relative, D. reticulatus. A brief diagnosis, illustration, and notes on the general biology of each species is provided. In addition, a key to the species of Dascyllus and tables of meristic and morphometric data are included.