Sieb is a surname and given name. Notable people with the name include:
Surname Armindo Sieb (born 2003), German professional football player John L. Sieb (1864–1941), American politician and barber Wally Sieb (1899–1974), American professional football player
Given name Sieb Dijkstra (born 1966), Dutch football coach and former professional footballer
See also Theodor Siebs (1862–1941), German linguist Siebs's law, a Proto-Indo-European (PIE) phonological rule