Siumu is a village on the central south coast of Upolu island in Samoa. The population is 1,092 (2006 Census). There is also a sub-village Siumu Uta which has a population of 206 (2006 Census).
Siumu Electoral Constituency (Faipule District) comprise the villages of Siumu, Siumu Uta, Maninoa and Saaga. The constituency has a total population of 2,224 and is part of the larger political district Tuamasaga.