Cycas pruinosa is a small to medium species of cycad. It is a widespread but sporadic species in the eastern and southern Kimberley region of Western Australia, occurring also in the Spirit Hills on Bullo River station in the Northern Territory.

This species is distinguished by its narrow glabrous leaflets with strongly recurved margins; its long, slender microsporangiate cones; and its long megasporophylls with long, sterile apices. It has a stout, erect trunk, around 2.5 m tall and 30 cm diameter, which is crowned with arching fronds, distinctly curved from the apex and V-shaped in cross-section. Glaucous leaf waxes may be either present or absent, causing plants to be either blue or green in overall appearance. It is suited to tropical regions which have a seasonally dry climate.

This strikingly distinctive and widespread species was only first recognised in 1978 by Australian botanist John Maconochie. The specific name, pruinosa, means "covered with powder" and aptly describes the blue-white ovules of this plant.