Siev or SIEV may refer to:
Suspected Irregular Entry Vessel, operational term used by the Australian Defence Force and Australian Coastwatch Siev., taxonomic author abbreviation of Johann August Carl Sievers (1762–1795), German-born botanist W.Siev., taxonomic author abbreviation of Wilhelm Sievers (1860–1921), German geologist and geographer David Siev, director of the American documentary film, Bad Axe
See also Sieve, a utensil SEIV, Space Empires IV, predecessor to Space Empires V