Due to the geographic dispersal of its recruits, the brigade initially opened its headquarters at the Sydney Showgrounds, while the constituent units remained at their home locations.

Arriving in Malaya in August 1941, under the command of Brigadier Duncan Maxwell, the brigade moved to Jemaluang,[7] as the 8th Division under Major General Gordon Bennett was tasked with securing the eastern part of Johore.

The brigade later participated in the Malayan Campaign following the Japanese invasion of Malaya in December 1941, although the initial stages of the fighting came in the north, away from the Australians' area of responsibility.

While the 22nd Brigade assumed control of eastern Johore, the 27th moved to the west where it was joined with several British and Indian units to create an ad hoc formation called "Westforce" under Bennett's command.

Together, as "Muar Force", they then fought to regain contact with the Indians and then began a fighting withdrawal towards the bridge at Parit Sulong, overwhelming several Japanese roadblocks as they went.

The 2/26th and 2/30th Battalions carried out delaying actions before withdrawing to Yong Peng, and then fought to maintain control of the cross road around Ayer Hitam.

On 28 January, further fighting occurred around the Namazie rubber plantation where the 2/26th repelled a strong Japanese attack, forcing them to carry out a flanking action that exploited a gap in the line to the west.

[4] At this time, the 2/29th Battalion, which had taken heavy casualties during the fighting in Malaya, subsequently received a large batch of partially trained reinforcements to make good its losses.

[11] Nevertheless, the attacking troops established a beachhead and the 27th Brigade's headquarters was subsequently cut off from its battalions, as the Allies were pushed back towards the centre of the island.

As the Allied perimeter continued shrink around the town, the 8th Division units were brought together around Tanglin Barracks, where they remained until the garrison surrendered on 15 February.