The present monarch is Elizabeth II, styled Queen of Australia, who has reigned since 6 February 1952. The monarch is represented in Australia as a whole by the Governor-General, in accordance with the Australian Constitution and letters patent from the monarch, and in each of the Australian states, according to the state constitutions, by a governor, assisted by a lieutenant-governor.

Głową Australii jest król Karol III. Australia jest jednym z królestw Wspólnoty Narodów (Commonwealth Realm), podobnie jak Kanada czy Nowa Zelandia, która związana jest unią personalną z Koroną brytyjską.