The 23rd Brigade was a brigade of the Australian Army. It was briefly raised in 1912 as a Militia formation providing training as part of the compulsory training scheme. Later, it was re-formed in July 1940 for service during the Second World War, the brigade was initially a formation of the Second Australian Imperial Force assigned to the 8th Division; however, after its sub units were captured by the Japanese in 1942 it was reformed with Militia battalions and was mainly used in a garrison role around Darwin, in the Northern Territory, until late in the war when it was committed to the fighting against the Japanese on Bougainville. It was disbanded in 1946.