Ajuga quadrangularis is a perennial herb with a height of 80 ~ 120 cm, erect stems, membranous wings at four edges, thin internodes, opposite branches and dark green. Sparse leaves, simple leaves opposite, short petiole; Leaf blade is small, ovate or ovate-lanceolate, 3-lobed, long 1 ~ 2 cm, wide 0.5 ~ 1 cm, sharp at the apex, wide wedge-shaped or round at the base, and the upper leaves gradually become smaller, shallow or undivided, with hairs on both sides. Flowers solitary in leaf axils, lavender; Pedicel slender, ca. 8 mm; Bracteoles 2, minute bit-shaped, hairy; Calyx bell-shaped, hairy, apex 5-lobed, lobes lanceolate; The corolla is 2-lipped and hairy, and the corolla tube is slender, about 65438 02 mm long, with 2-cleft upper lip and 3-cleft lower lip. 4 stamens, extending out of corolla tube, parallel, with hairs at the lower end of filaments; Ovary 4-lobed, hairy, style from the base of ovary, apex 2-lobed. Four little nuts. The flowering period is from May to June, and the fruiting period is from June to September.