Radha Mitchell (born November 12, 1973 in Melbourne, Victoria, Australia) is an Australian actress. She has been referred to as "Small, blonde, and Australian", standing 1.67 m (5 ft 6 in).

Mitchell attended St Michael's Grammar School.

Mitchell first got her start in acting in the role of Cassandra Rushmore on the long-running Australian soap opera Neighbours in 1994. In 1996–97, she starred as Catherine O'Brien on the same show. She starred as pilot Fry in the science fiction movie Pitch Black (2000), which was filmed in Australia.

Woody Allen personally called her mobile phone to offer her the role of Melinda in Melinda and Melinda (2004). She was convinced that it was a prank until the script was delivered to her.