Polyscias gymnocarpa is a tree that grows to heights between 2.5 and 10 meters. It features compound (pinnate) leaves that are alternate in arrangement. Each leaf consists of 7 to 21 (occasionally up to 25) leaflets, which are ovate to oblong-elliptic in shape and often folded upward along the midvein. Leaflets typically measure 7 to 18 cm in length and 3 to 8 cm in width, with the lower pairs being smaller and ovate. The leaflets have rounded or obliquely acuminate apices, and their bases range from rounded to truncate or subcordate, often obliquely. The leaf surfaces are glabrous, although young leaves and inflorescences may exhibit mealy stellate pubescence. The leaf margins are entire, and the leaflets are supported by petiolules measuring 5–15 mm long. Stipules are absent or rudimentary. The inflorescences are erect, racemose–umbellate, with a stout primary axis, measuring 2–8 cm long. The secondary axes, or rays, are 3–5 in number, divergent, and 10–35 cm long, with ultimate branches 4–12 cm long, arranged umbellately at the tip and racemosely along the rays. The lateral branches are often early caducous, leaving a visible scar. The flowers are bisexual (perfect) and actinomorphic, with terminal (frequently appearing lateral) positions. The pedicels are 5–10 mm long and can elongate up to 14 mm in fruit. The calyx presents as a short rim with 6(7) teeth. The corolla consists of 5–6(7) lanceolate petals measuring 4–8 mm long, and the stamens number 5–6(7). The ovary is (2)3–4(5)-carpellate, appearing entirely superior due to the expansion of the disk and reduced development of the hypanthium, with stigmas as numerous as the carpels and sessile. The fruits are drupes, purplish at maturity, and range from ovoid to oblong–turbinate, occasionally globose, measuring 6–12 mm long. The pyrenes are papery, and the seeds are one per pyrene, containing a small embryo. It is found in wet to sometimes mesic forests between 250-850 meters.