It is a recently described plant, previously included with P. fitzgeraldii, but distinguished from that species by its smaller, less crowded flowers, with more spreading lateral sepals and different labellum callus.

There is an egg-shaped, shiny, yellowish-green callus in the centre of the labellum and extending past its bend.

[2][3] Prasophyllum roseum was first formally described in 2017 by David Jones and Robert Bates and the description was published in Australian Orchid Review from a specimen collected in the Desert Camp Conservation Park.

[1] The specific epithet (roseum) is a Latin word meaning "of roses",[4] referring to the colour of the labellum.

[2] The pink lip leek orchid grows in damp heathy woodland and forest in the southeast of South Australia and in western Victoria near Edenhope, Nhill and Stawell.