Freycinetia arborea is a woody climber that ascends trees or rocks or sometimes sprawls on the ground. The stems, which can be up to approximately 2.5 cm in diameter, are noticeably ringed with persistent leaf scars. The plant features clasping, often flattened, sometimes long and wiry adventitious roots that wrap around the climbing surface. The leaves are simple, alternate, spiraled in 3-ranked clusters toward the branch ends, with linear-lanceolate blades typically measuring 40–80 cm in length and 1–3 cm in width. The leaves gradually attenuate at the apex and have a sheathing base with narrow, tapered, usually pale green auricles up to 11 cm long, often abraded or caducous. The leaf surfaces are glabrous and coriaceous, with margins near the auricles minutely serrulate with prickles 0.2–0.6 mm long. The numerous parallel, longitudinal veins form a reticulate pattern through perpendicular commissures. It produces terminal inflorescences with bracts ranging from green with a salmon–orange base to dark salmon–pink and pink inner bracts. The plant is dioecious, with pistillate spadices typically in clusters of three or four on stout, trigonous peduncles, and staminate spadices also in clusters, with yellowish-white, densely crowded stamens. The fruit is a red, compressed, oblong berry, up to 10 mm long, with ellipsoid seeds up to 1.5 mm long. It occurs in mesic to wet forests, often found on exposed ridges and slopes between 300-1,500 meters.