The 54th Battalion was an infantry battalion of the Australian Army. It was originally raised in 1916 for service during World War I and took part in the fighting in the trenches of the Western Front in France and Belgium before being amalgamated with the 56th Battalion in late 1918 following the German Spring Offensive that reduced the numbers in both battalions. The battalion was re-raised in 1921 as a part-time unit in New South Wales before being amalgamated with the 20th Battalion in 1929. At the outbreak of World War II, the battalion was reformed in its own right, undertaking garrison duties in Australia until being disbanded in 1944.