The 6th Motor Brigade was a militia formation of the Australian Army, which was formed during World War II.

Following the invasion of Malaya, attack on Pearl Harbor and fall of Singapore, the 6th was called up for full-time service, carrying out defensive duties in Australia.

The evolution of Australia's mounted forces, the Australian Light Horse, had lagged well behind that of other countries who had converted their horse mounted cavalry to motorised (trucks) or mechanised (armoured fighting vehicles) forces in the 1930s and 1940s, but the advent of war provided the impetus for change.

[2] In the early phase of the war, the brigade was tasked with forming a district reserve, and defending positions along the Onkaparinga and Sturt Rivers, in South Australia.

They subsequently joined the 3rd Motor Brigade and other divisional troops,[5] in Victoria, concentrating in Gherang in June before moving to Puckapunyal in July to begin receiving armoured vehicles.