Allocasuarina microstachya is a shrub of the genus Allocasuarina native to a small area in the Mid West, South West, Wheatbelt and Goldfields-Esperance regions of Western Australia. The dioecious intricate shrub typically grows to a height of 0.1 to 1 metre (0.3 to 3.3 ft). It produces yellow-red-brown flowers from August to January and is found in sandy and gravelly lateritic soils.