Cyanea aculeatiflora is a palm-like tree growing 2–7 meters tall, characterized by white, yellow, or tan latex. Its stems are either unarmed, muricate, or aculeate. The leaves are simple and alternate, with oblanceolate, oblong, or elliptic blades measuring 40–100 cm in length and 10–21 cm in width, featuring a rounded or obtuse apex, an obtuse or cuneate base, and callose-denticulate margins. The upper leaf surfaces are glabrous or sparsely muricate along the veins, while the lower surfaces are pubescent and muricate on the veins. Petioles are 10–18 cm long and muricate. The plant produces 5–10-flowered inflorescences, muricate and clustered among the leaves, with peduncles 40–100 mm long and pedicels 10–15 mm long. The flowers are bisexual, with a calyx having five oblong lobes, 10–25 mm long, and a zygomorphic corolla that is blackish purple externally and white or pale lilac within, measuring 60–85 mm long. The staminal column is magenta, and the anthers are dark purple. The ovary is inferior and 2-celled, leading to berries that are yellow to yellowish orange, obovoid or ellipsoid, 20–25 mm long, and 17–20 mm wide, with numerous small, brown to black seeds, about 0.2 – 0.5(-2) mm long, with a short to spatulate dicotyledonous embryo embedded in oily endosperm. This species is found in wet forests at 945–1,450 meters.