The 5th Motor Brigade was a formation of the Australian Army during the interwar years and World War II. A formation of the part-time Militia, the brigade was formed in 1921 as the 5th Cavalry Brigade. At this time, it consisted of three light horse regiments based in Victoria. The brigade ceased to exist in 1936 due to manpower shortages, but was re-raised during World War II, in April 1942, as a motor brigade. It was quickly disbanded, however, and was used to raise the 6th Armoured Brigade in June 1942, without having seen combat.