It has a single fleshy, light green leaf and up to nine greenish flowers with reddish stripes.

Calochilus paludosus is a terrestrial, perennial, deciduous, herb with an underground tuber and a single fleshy, light green to yellowish-green, linear to lance-shaped leaf which is 100–180 mm (4–7 in) long and 4–7 mm (0.2–0.3 in) wide.

Unlike some others in the genus, the leaf is fully developed at flowering time.

[2][3][4][5] Calochilus paludosus was first formally described in 1810 by Robert Brown and the description was published in Prodromus Florae Novae Hollandiae.

[6][7] The specific epithet (paludosus) is a Latin word meaning "boggy" or "marshy".