It has a single tubular leaf and up to eighteen scented, greenish flowers with a white labellum.

It is a distinctive species of leek orchid with its green and white, crowded flowers.

[2][3][4] Prasophyllum wallum was first formally described in 1991 by Robert Bates and David Jones from a specimen collected near Coolum and the description was published in Australian Orchid Research.

[2][3] Prasophyllum wallum is listed as "Vulnerable" under the Commonwealth Government Environment Protection and Biodiversity Conservation Act 1999 (EPBC) Act and the Queensland Nature Conservation (Wildlife) Regulation 2006.

The main threat to the species are habitat loss, inappropriate fire regimes and illegal collecting.