Acacia coolgardiensis, commonly known as sugar brother or spinifex wattle, is a shrub in the family Fabaceae.

Endemic to Western Australia, it is widely distributed in the semi-arid spinifex country from Carnarvon to Kalgoorlie.

These are green, and may be up to 10 centimetres long and about three millimetres wide.

The flowers are yellow, and held in cylindrical clusters up to two centimetres long and five millimetres wide.

It was first published by Joseph Maiden in 1920, based on a specimen collected by Leonard Clarke Webster near Coolgardie in 1900, and a description of the fruit near Kununoppin supplied by Frederick Stoward.