Charpentiera densiflora is a tree species that can grow up to 12 meters tall, characterized by new brown and tomentose growth. The stems measure 4–9 mm in diameter directly below the apex. The leaves of this tree are simple, alternate, and range from elliptic to sub-ovate in shape. They are 13–40 cm long and 5.5–9.5 cm wide, with an obtuse apex and an acute base. The surfaces of the leaves can be either glabrous or pubescent, coriaceous, or somewhat so. The margins are entire, slightly wavy with pronounced marginal ribs. Approximately 20 pairs of lateral veins become glabrous at maturity, and the marginal vein is somewhat developed. The petioles are 3–18.5 cm long, and stipules are absent. The flowers appear in single axillary panicles that are 1–2 branched and can be reddish-brown pubescent or glabrous. The panicles are 22–48 cm long with 9–32 primary branches, each 3.5–15 cm long, and each branch is subtended by one bract and two bracteoles. The peduncles are 2–15 cm long. The plant is gynodioecious, with populations having both bisexual (perfect)–flowered plants and female plants. There are 20–100 flowers per branch, with internodes between individual flowers measuring 1–5 mm long. The calyx has five distinct, imbricate, subequal sepals, 1.75–2.1 mm long and 3–5-veined. The corolla (petals) is absent. Five stamens and staminodes with filaments form a short, membranous tube. The anthers are exserted at anthesis. The ovary is superior, globose or urceolate (pitcher-shaped), 1.5–2 mm long, with an absent or concise style and two straight or recurved stigmas nearly as long as the ovary, with glands on the inner surface. The fruit is an indehiscent utricle with black and shiny lenticular seeds measuring 1 mm or less in length. It is found in mesic gulches of Pandanus forests and can sometimes be a dominant vegetation feature. It grows at elevations of 160–250 meters.