Sigrid Thornton (born 12 February 1959) is an Australian actress. Her television work includes Prisoner (1979–80), All the Rivers Run (1983), SeaChange (1998–2000) and Wentworth (2016–). She also starred in the American Western series Paradise (1988–91). Her film appearances include Snapshot (1979), The Man from Snowy River (1982), Street Hero (1984) and Face to Face (2011). She won the AACTA Award for Best Guest or Supporting Actress in a Television Drama for the 2015 miniseries Peter Allen: Not the Boy Next Door
Thornton was born in Canberra, the daughter of Merle, a teacher and writer, and Neil Thornton, an academic. She was raised in Brisbane, attending St. Peter's Lutheran College. For two years she lived in London, where she was a member of the Unicorn Theatre.
Back in Brisbane she attended Twelfth Night Theatre Junior Workshop and In 1970, during the Captain Cook Bicentenary Celebrations, Thornton appeared before Queen Elizabeth II as Rosa Campbell-Praed in Looking Glass on Yesterday. She acted in TV series Homicide and Division 4 in 1975. She also appeared on The Sullivans, as Elizabeth "Buffy" Turnbull.