Acacia trinervata commonly known as three-veined wattle,^[4] is a species of flowering plant in the family Fabaceae and the subgenus Phyllodineae. It is a tall shrub with angular branchlets, bright yellow flowers and grows in New South Wales.

Acacia trinervata is an erect or spreading shrub growing to a height of 1.5–3 m (4.9–9.8 ft). Its branchlets are smooth and angle towards the apex. The phyllodes are very narrowly elliptic to linear with a pointed sharp tip, 1.5–5 cm (0.59–1.97 in) long, 1–3 mm (0.039–0.118 in) wide and 2 or 3 prominent longitudinal veins. There is an inconspicuous gland 0–3 mm above the base, and the pulvinus is less than 1 mm long. The inflorescences are simple, occurring singly in the phyllode axils on peduncles about 10–20 mm long. The 20 to 30 bright yellow flowers are 5 to 7.5 mm in diameter. Flowering occurs from March to June and the fruit is a papery to thinly leathery pod, slightly swollen above the seed, minutely hairy, 6–12 cm (2.4–4.7 in) long and 1–3 mm (0.039–0.118 in) wide.^[4]

Three-veined wattle grows in open forest on sandstone and shale and is endemic to New South Wales and restricted to western Sydney and the lower Blue Mountains. ^[5]

The species was first described in 1825 by Franz Sieber,^[1][2] and the specific epithet trinervata derives from the Latin for "three veined".^[4]

• Acacia trinervata images on Flickr