Schoenoplectiella juncoides is an annual or short-lived perennial, sometimes with short rhizomes. The culms are pale green, dull, densely tufted, subterete (not precisely cylindrical), or obtusely several-angled, standing 15–70 cm tall and 1–4 mm in diameter below. This plant has a fibrous root system. The leaves are simple, reduced to 3–4 bladeless sheaths with entire margins and sheathing; the lower sheaths are brown and scale-like, while the upper sheaths are pale green and can be up to 15 cm long. Stipules are absent. The flowers are in anthelate, umbel-like inflorescences with 2–10 spikelets. Involucral bracts are erect, measuring 5–15 cm long, with a furrow on the upper surface toward the base. Spikelets are pale yellowish-brown, sessile, oblong to ovoid-oblong, 6–18 mm long, and 3–6 mm wide. The glumes are pale brown and membranous, ovate to elliptic-ovate, 3–4 mm long, 1.8–2.5 mm wide, weakly 3-nerved with green nerves, and have a subentire, mucronate apex. Bristles are 4–6 in number, with 4 as long as or slightly surpassing the achene. The flowers are bisexual (perfect), without petals, and have 3 stamens. The ovary is superior. Fruits are nutlets, dark brown at maturity, broadly obovate, about 2 mm in size, plano-convex, and obscurely transversely wrinkled. Achenes are dark brown, broadly obovate, lenticular, 1.8–2 mm long, about 1.5 mm wide, and transversely wrinkled. Seeds are singular per fruit, with a thin seed coat, free from the pericarp (part of a fruit formed from the wall of the ripened ovary), basal embryo, and abundant endosperm. It is found in bogs, pond margins, and wet forests between (5-)180-1,370 meters.