A large number of reports on mosquitoes of Sumatera and neighbouring islands reveal that 198 species have thus far been discovered (Brug & Haga, 1923; Brug, 1931; Brug & Edwards, 1931; Swellengrebel & Rodenwaldt, 1932; Brug, Bonne-Wepster, 1947; Bonne-Wepster & Swellengrebel, 1953; Bonne-Wepster, 1954; Waktoedi, 1954; Reid, 1968; Lien et al., 1975). All these report were based on short-term surveys, and most were from South Sumatera. Longitudinal studies of mosquito vectors of malayan filariasis during this study for a 24-month period in two villages were carried out. All mosquito species were collected, identified and recorded. The present paper presents the mosquito fauna in the study areas, and discusses (1) the seasonal variations of Culex tritaeniorhynchus, Anopheles peditaenia-tus, and An. Nigerrimus, and (2) the parous rate of two Anopheles species.