The AACTA Award for Best Actress in a Supporting Role is an accolade given by the Australian Academy of Cinema and Television Arts (AACTA), a non-profit organisation whose aim is to "identify, award, promote, and celebrate Australia's greatest achievements in film and television". Toni Collette and Judy Davis are the most awarded actresses in this category, with three wins each. Candidates for this award must be human and female, and cannot be nominated in the leading actress category for the same role in the same production.