Acacia websteri is a shrub or tree belonging to the genus Acacia and the subgenus Juliflorae that is endemic to western Australia.
The shrub or tree typically grows to a height of 1.2to and produces yellow flowers. The branchlets flattened near the tips and are sparsely haired to glabrous and occasionally white-resinous. Like most species of Acacia it has phyllodes rather than true leaves. The thinly coriaceous evergreen phyllodes are erect with a linear shape and length of and a width of . They taper to a point with a gently curved apex and have three nerves per face. When the plant blooms it produces simple inflorescences with obloid to sub-spherical flowerheads that have a length of and a diameter of containing 30 to 36 golden coloured flowers. The narrowly linear seed pods that form after flowering have longitudinal ridges and are straight and biconvex with a length of up to and a width of containing longitudinally arranged seeds. The light brown seeds have an oblong shape with a length of around and a terminal aril.[1]
It is native to an area in the Wheatbelt and Goldfields regions of Western Australia. It has a disjunct distribution from around Bencubbin and around the towns of Coolgardie and Kambalda where it is often situated in drainage depressions growing in red loam, sand and clay soils as a part of shrubland and scrub communities.[1]