Swainsona swainsonioides is a perennial, spreading herb up to 50 cm (20 in) high with stems covered densely or sparingly with hairs.

The leaves are mostly 3–12 cm (1.2–4.7 in) long, leaflets 11-21, narrow to broadly egg-shaped to elliptic, sometimes lance-shaped, 5–20 mm (0.20–0.79 in) long, 4–10 mm (0.16–0.39 in) wide, apex pointed or rounded, upper surface usually smooth, lower surface with short soft hairs.

Flowering occurs mostly from May to November and the fruit is an elliptic-oblong shaped pod 15–35 mm (0.59–1.38 in) long, apex rounded, smooth, green to brown and containing up to 40 seeds.

[2][3] This species was described in 1848 by George Bentham who gave it the name Cyclogyne swainsonioides in Thomas Mitchell's Journal of an Expedition into the Interior of Tropical Australia.

[4][5] In 1948 John McConnell Black transferred the species to the genus Swainsona as S. swainsonioides in the Flora of South Australia, from an unpublished description by Alma Theodora Lee.