Conostephium marchantiorum is a species of flowering plant in the heath family Ericaceae and is endemic to the south-west of Western Australia.

It is an erect shrub with linear leaves clustered near the ends of branchlets, and pale green and pink, densely-bearded, tube-shaped flowers.

Conostephium marchantiorum is an erect shrub that typically grows to a height of about 1 m (3 ft 3 in) and has many branches, its leaves clustered near the ends of twigs.

[2][3] Conostephium marchantiorum was first formally described in 1986 by Arne Strid in the journal Willdenowia from specimens he collected near Scaddan in 1983.

[3] Leucopogon marchantiorum is listed as "Priority Three" by the Government of Western Australia Department of Biodiversity, Conservation and Attractions,[3] meaning that it is poorly known and known from only a few locations but is not under imminent threat.