A slow-growing tree fern, forming a thick, sometimes massive trunk up to 15 m tall. The trunk is usually solitary but may produce offsets, and is densely covered in matted, brown aerial roots, with persistent leaf bases towards the crown. The trunk apex and leaf bases are densely covered with glossy ginger-brown hairs up to 4.5 cm long.
The numerous leaves are borne in a large, spreading crown. The leaf bases are warty or smooth, and the midrib bears sparse, long, brown, shaggy hairs. The leathery leaf blade is 2-4 m long, divided three times, dark green and shiny above, and paler. There is one sorus (structure bearing sporangia, which contain spores) per lobe. The indusia (flaps of tissue covering the sorus) are composed of two lips, more or less equal in size.
Australian tree ferns are slow-growing – between 1-10 cm per year depending on conditions – and do not reach maturity until they are about 23 years old.