Acacia dawsonii is an erect shrub growing to a height of 0.5 to 4 metres (2 to 13 ft), with appressed branchlets that are hairy between resinous ridges.

The evergreen phyllodes are straight to slightly curved with a very narrowly elliptic to linear shape and a length of 4 to 11 cm (1.6 to 4.3 in) and a width of 2 to 5 mm (0.079 to 0.197 in) with up to ten longitudinal veins of which one or two are usually more prominent that the others.

The golden yellow flowers are borne in racemes in leaf axils, peduncles 1–3 mm (0.039–0.118 in) long and globular.

Flowering occurs from September to October and the fruit is a linear pod up to 6 cm (2.4 in) long, 2–5 mm (0.079–0.197 in) wide, straight or with a slight curve, stiff, leathery and smooth.

[2][3] Acacia dawsonii was first formally described in 1897 by Richard Baker and the description was published in Proceedings of the Linnean Society of New South Wales.