Acacia idiomorpha is a shrub belonging to the genus Acacia and the subgenus Phyllodineae. It is native to an area along the west coast in the Wheatbelt and Mid West regions of Western Australia. The spreading spinescent shrub typically grows to a height of 0.2 to 1.0 metre (0.7 to 3.3 ft) and produces yellow flowers from July to August.