Acacia crassiuscula is a shrub belonging to the genus Acacia and the subgenus Phyllodineae. It is native to an area along the south coast in the Goldfields-Esperance, Great Southern and South West regions of Western Australia. The erect and spindly shrub typically grows to a height of 1 to 2.5 metres (3.3 to 8.2 ft). It blooms from July to October and produces cream-yellow flowers.