Senna barclayana is an erect, herbaceous perennial subshrub that typically grows to a height of up to 1.5 m (4 ft 11 in).

There is a sessile gland near the base of the petiole, and a stipule that falls off as the leaf opens.

Flowering occurs all year, and the fruit is a cylindrical pod 30–50 mm (1.2–2.0 in) long.

[2][3][4] This species was first formally described in 1827 by Robert Sweet who gave it the name Cassia barclayana in his Flora Australasica.

[6][8] Senna barclayana grows in open forest southern Queensland and northern New South Wales, but its range is increasing and it is now naturalised in Victoria, South Australia and Western Australia.