Acacia phasmoides, commonly known as phantom wattle, is a shrub species that is endemic to south-eastern Australia. It grows to between 1 and 4 metres high and has phyllodes that are 5 to 12.5 cm long and 1 to 2 mm wide. The bright yellow globular flowerheads appear singly or in groups of two in the axils of the phyllodes from September to November, followed by curved seed pods which are 5 to 9 cm long and 2 to 4 mm wide.
The species was formally described in 1967 by botanist Jim Willis based on plant material collected from Pine Mountain in north-eastern Victoria. Its distribution is limited to a small area on the border between south-eastern New South Wales and north-eastern Victoria.