The bark is rough, yellow to grey-brown and frequently fissured and the stem is rarely thicker than 230 mm. The twice-compound, petiolate leaves are very variable in size with 4 to 19 pairs of pinnae and each pinna with 9 to 41 pairs of leaflets, giving it an Acacia-like appearance. The petioles (leaf stalks) are up to 50 mm long and the leaf length varies between 10 and 160 mm. The young twigs are slightly hairy and a characteristic feature is that the spines are not modified stipules but hardened branchlets, ending in a straight, sharp point.

The flowers are 25 to 50 mm long, pendulous spikes that are borne in the leaf axils, singly or in bundles. The pleasant-smelling fluffy flowers are lilac in the upper half and yellow in the lower, giving rise to the descriptive name Chinese lantern tree in other countries. Its flowering season is spring, generally from September to February.

Each flower produces a mass of flat, coiled green pods that turn brown and later fall to the ground. Each pod contains a large number of seeds; young pods are curved, resembling sickles.