The trunk is very rough with the persistent leaf bases clasping the stem as layers of coarse fibrous material. It is a fan palm with the leaves with the long petiole bare except for two rows of small spines, terminating in a rounded fan of numerous leaflets; each leaf is 140–190 centimetres (55–75 in) long, with the petiole 60–100 centimetres (24–39 in) long, and the leaflets up to 90 centimetres (35 in) long. It is a somewhat variable plant, especially as regards its general appearance and some specimens are to be seen with leaf segments having straight and others having drooping tips.
The flowers are yellow (male) and greenish (female), about 2–4 millimetres (0.079–0.157 in) across, borne in large branched panicles up to 1 metre (3 ft 3 in) long in spring; it is dioecious, with male and female flowers produced on separate trees. The fruit is a yellow to blue-black, reniform (kidney-shaped) drupe 10–12 millimetres (0.39–0.47 in) long, ripening in mid autumn.
Occasionally a male plant of T. fortunei, besides the usual spadices, produces a few other spadices carrying really hermaphroditic flowers. Completely fertile, these are almost exactly like the male flowers, but are a little larger and with the carpels well evolute, the latter about as long as the filaments, furnished with a ring of silvery hairs all round.