Claudia has acted in Australian and New Zealand television and movies. She portrayed a hermaphrodite named Jill Mayhew in the Australian television series Good Guys Bad Guys. She also had a leading role in the New Zealand soap opera City Life playing the role of Greek lawyer Angela Kostapas.
For her roles in Farscape, Black was nominated for a Saturn Award in the Best Actress category in both 2001 and 2002, and won the award in 2005. She has appeared in the feature films Queen of the Damned and Pitch Black. Black also appeared as Vala Mal Doran in Stargate SG-1 as a regular cast member in the tenth and final season, and previously had a role as a recurring character in season 8 and season 9. Her first appearance was in the episode "Prometheus Unbound". Black has starred in two Stargate SG-1 Direct-to-DVD movie spin-offs, Stargate: The Ark of Truth and Stargate: Continuum respectively, but will not return for a third installment. In 2004, she was voted "#7 Hottest Scifi Babe" by Scifi WorldNet.