Ellen Niit (born Ellen Hiob; Ellen Niit since 1958) (13 July 1928 – 30 May 2016) was an Estonian children's writer, poet and translator. Over her lifetime, she penned more than forty books of both prose and poetry for children. She also wrote a number of collections of prose and poetry for adults. Her works have been translated into eighteen languages.

Niit was born in 1928 in Tallinn, Estonia. She attended school in Tapa and in Tallinn, then graduated from the University of Tartu in the field of Estonian philology in 1952. After working as a poetry consultant at the Writers' Union of the ESSR from 1956 to 1961, she was forced to resign for ideological reasons. Afterward, Niit worked as an editor of children's television programmes, and in 1963 became a freelance translator and writer.

Hiob first married folklorist and literary scholar Heldur Niit in 1949. They had one son, noted psychologist Toomas Niit, in 1953. The couple divorced in 1958, the same year she wed writer Jaan Kross; their children are Maarja Undusk (born 1959), Eerik-Niiles Kross (born 1967) and Märten Kross (1970).