The 2/4th Pioneer Battalion was a unit of the Australian Army raised for service during the Second World War. An pioneer unit, the battalion undertook both infantry and engineer tasks. Despite being raised early in the war, the battalion did not see action until the final months, taking part in the Borneo campaign where, as part of the 1st Beach Group, it fought against the Japanese in support of the 9th Division. It was disbanded in early 1946 following the end of hostilities.