Katherine Margaret Ellis (born 22 September 1977) is a former Australian politician, who represented the Division of Adelaide in the Australian House of Representatives for the Australian Labor Party from 2004 until 2019. She served in multiple portfolios in the outer ministry of the 2007–2013 federal Labor government and was in the shadow cabinet after that. In March 2017 Ellis announced that she would step down from shadow cabinet as of the next reshuffle and leave parliament at the 2019 federal election.