Elaeocarpus williamsianus, commonly known as hairy quandong,[2] is a species of flowering plant in the family Elaeocarpaceae and is endemic to a restricted area of north-eastern New South Wales.

Elaeocarpus williamsianus is a tree that typically grows to a height of 9–15 m (30–49 ft) with a trunk diameter of up to 18 cm (7.1 in), with creamy-brown bark but without buttress roots.

Flowering occurs from November to December and the fruit is a more or less spherical blue drupe about 20–30 mm (0.79–1.18 in) in diameter, the stone with three longitudinal grooves.

[2][3][4][5] Elaeocarpus williamsianus was first formally described in 1983 by Gordon Paul Guymer in the journal Telopea from specimens collected near Burringbar in 1980.

[4] Hairy quandong is restricted to nine sites on the Burringbar Range in the far north-east of New South Wales, where it grows in warm temperate rainforest, including in disturbed areas where it has regrown from root suckers.