Cyrtandra gracilis is a shrub with branching stems rounded to angular and covered in multicellular hairs, which may become smoother (glabrate) over time. The leaves are simple and opposite, attached to the stem’s upper 4–6 nodes, with each pair of leaves being somewhat unequal yet symmetrical or nearly so. The leaves are elliptic-ovate, measuring 11.5–22 cm in length and 3.6–6.6 cm in width, with a long-acuminate apex and an attenuate base. The leaf surfaces are sparsely covered with white, hemispherical, subsessile glands, eventually becoming glabrate, and the blades are firm-chartaceous. The margins are serrated. Petioles are 2.5–8.5 cm long, occasionally clasping the stem. The inflorescence comprises 1–7 flowers open to very open umbelliform cymes arising from the leaf axils, with peduncles 8–22 mm long and pedicels 15–75 mm long, apparently sigmoid. The calyx is nearly actinomorphic (radially symmetric), 14–36 mm long, with linear lobes that are somewhat unequal and sparsely covered with subsessile glands, becoming glabrate. The corolla is usually bilabiate and white, about 22–24 mm long and 3–5 mm in diameter, with subsessile glands more densely populated in the bud. The upper lip of the corolla is 2-lobed, while the lower lip has three lobes. It has five stamens, with two upper fertile stamens and the others being staminodial. The ovary is superior, covered with sub-sessile glands at the apex and glabrous below, leading to a fleshy or firm white berry that is narrowly ovoid, approximately 2.3–2.5 cm long, often maintaining the persistent stylar beak. It occurs in wet forests.