The minister for Defence, also known as the Defence minister, is the minister of state of the Commonwealth of Australia charged with overseeing the organisation, implementation, and formulation of strategic policy in defence and military matters as the head of the Department of Defence. The Defence minister directs the government’s approach to the Australian Defence Organisation and the Australian Defence Force. The current Defence minister is Richard Marles, who is concurrently serving as deputy prime minister of Australia, he was selected by Prime Minister Anthony Albanese in May 2022 following the 2022 Australian federal election.

Defence Australia is a department of the Government of Australia charged with the responsibility to defend Australia and its national interests. Along with the Australian Defence Force (ADF), it forms part of the Australian Defence Organisation (ADO) and is accountable to the Commonwealth Parliament, on behalf of the Australian people, for the efficiency and effectiveness with which it carries out the Government's defence policy.