Nothocestrum peltatum is a small tree, reaching heights of up to 5 meters, with a distinctive glabrous and brightly ashy-brown bark. The flowering stems are relatively thick, about 6–7 mm in diameter, and are covered with a dense layer of tomentum. The leaves are simple and alternate, with various shapes, including ovate to ovate-elliptic, ovate-oblong, or oblong, and range in size from 6–23 cm in length and 3.5–7.5 cm in width. The peltate leaves have an obtuse apex to rounded, occasionally emarginate, and a broadly rounded or truncate and inequilateral base. The upper surfaces of the leaves are puberulent along the midrib, while the lower surfaces are densely tomentose on the veins, with the hairs having a yellowish tint. The blades are coriaceous, and the margins are either entire or slightly sinuate. The flowers form in axillary clusters, with up to 10 flowers per cluster, are bisexual, actinomorphic (radially symmetric), and pedicellate, featuring a more or less oblique calyx 10–18 mm long, 3–4 teeth, and externally tomentose. The corolla is presumed greenish-yellow, with an exserted tube, 12–14 mm long, and four fleshy lobes broadly ovate and densely tomentose. There are four stamens, slightly exserted, with extremely short to absent filaments, and linear, acute anthers that open longitudinally. The superior ovary is 2-celled, conical-cylindrical, with numerous ovules, an approximately 3.5 mm long style, and a 2-lobed stigma. The fruit is an orange berry, ellipsoid in shape, measuring 13–14 mm in length with a truncate apex. The seeds are numerous and irregular in outline, angular, with an impressed-punctate seed coat measuring 1–1.5 mm in diameter. It is rare, known only from mesic habitats between 915-1,220 meters.