An historical review is given of the work done on the mosquitoes of Samoa and Tonga. A total of 15 species belonging to the genera Aedes, Culex, Coquillettidia and Toxorhynchites is known to occur in the area, 13 species in Samoa and 8 in Tonga. Information for each species is provided with respect to the original description, stages described, biology and distribution. Where necessary, a taxonomic discussion is provided. Keys for the identification of adults, male genitalia, pupae and larvae are provided.