Rhizomes to 1 m or longer, remaining below ground. Culms 2–8 m tall, 1-4 cm thick, erect or nodding, diffuse and solitary in open spreading thickets; lower nodes usually thorny, prominent; internodes to 20 cm, more or less strongly quadrangular in cross-section, lightly scabrous or tubercular, remaining matt green. Branches 3, short, budscale of two short, single-keeled bracts. Culm sheaths shorter than the internodes, quickly deciduous, thin, glabrous, edges ciliate, veins elevated, conspicuously purple-tessellated and spotted; auricles and oral setae absent; blades 1–3 mm, triangular to acicular. Leaf sheaths deciduous, glabrous, edges ciliate; ligule very short, to 1 mm, truncate, pubescent; auricles absent; oral setae up to 5 each side, erect, white, to 5 mm; blades to 15 cm long, to 1.5 cm wide, conspicuously tessellate, abaxial and adaxial glabrous, petiole glabrous. Spikelets (1–)2–4, 2–3 cm, slender; florets 2–5, basal 0–2 rudimentary. Name from the quadrangular culms.
Cultivars with yellow culms striped green and some variegated leaf blades are also available.
Widely distributed in W. China, Chimonobambusa quadrangularis is now cultivated in many countries. A resilient bamboo, hardy to -13°C, it thrives in warmer climates, where it can spread aggressively. It is considered an invasive naturalised weed in Hawaii. Although Tetragonocalamus angulatus (Munro) Nakai and Chimonobambusa angulata (Munro) Nakai are widely assumed to be synonyms of Chimonobambusa quadrangularis, it has been known for some time that they are actually synonyms of Bambusa breviflora Munro, itself now considered to be a synonym of B. tuldoides.
Chimonobambusa quadrangularis was introduced into Europe from China in the 19th Century, original location unknown.