Justine Clarke is an Australian actress, singer, author and television host.

Clarke has been acting since the age of seven and has appeared in some of Australia's best-known TV shows. She is best-known for her portrayal as Roo Stewart on the soap opera Home and Away (1988–1989), as Ally Kovac on the drama series Tangle (2009–2012), and as a presenter on the Australian children's show Play School, a role which she has held since 1999. She is also a film and stage actor, and won the Best Actress Award at the Mar del Plata International Film Festival in Argentina in 2006 for her role in independent film Look Both Ways. She has won two ARIA Awards.