Plants perennial. Culms 30-300 cm, erect. Blades to 30 cm long, 1-8 mm wide. False panicles 20-50 cm; sheaths subtending the rame clusters 1.5-3.5 cm, reddish, glabrous or pilose, hairs papillose-based; rames 15-20 mm, with 1 heterogamous spikelet pair. Homogamous spikelets 6-14 mm, glabrous or with papillose-based hairs. Sessile heterogamous spikelets 6-14 mm; calluses 2-4 mm, with rufous hairs; lower glumes mostly smooth, glabrous, apices appressed-pubescent; awns 2.5-7 cm; pedicellate spikelets 6-14 mm, glabrous or with papillose-based hairs. 2n = 20, 21, 22, 24, 40, 60, 70, 80.

Themeda triandra is native to India, Korea, China, and Japan. Many infraspecific taxa have been described in T. triandra and in T. australis (R. Br.) Stapf, a species that is sometimes included in T. triandra. Themeda triandra subsp. japonica (Willd.) T. Koyama is sold as an ornamental in the Flora region but, in the absence of a treatment that covers both species throughout their range, it is impossible to state how it differs from other members of the complex.