Swainsona canescens is an ascending or upright perennial herb with stiff stems over 20 cm (7.9 in) long and more than 3 mm (0.12 in) wide near the base.

The leaves are 5–12 cm (2.0–4.7 in) long, usually with 10-13 egg-shaped or broadly elliptic to oblong leaflets, 10–20 mm (0.39–0.79 in) long, 5–15 mm (0.20–0.59 in) wide, almost smooth on upper surface or with silky hairs on both surfaces and occasionally with a triangular, short point or slight notch.

Flowering occurs in May or July to December and the fruit is a pod 10–15 cm (3.9–5.9 in) long and about 4 mm (0.16 in) wide, densely covered in short, matted hairs and containing up to 10 seeds.

[3][2] This species was described in 1839 by John Lindley, who gave it the name Cyclogyne canescens in A Sketch of the Vegetation of the Swan River Colony, from an unpublished description by George Bentham.

[4][5] In 1862 Ferdinand von Mueller changed the name to Swainsona canescens and the description was published in Fragmenta Phytographiae Australiae.