Lasiopetalum rosmarinifolium is a species of flowering plant in the family Malvaceae and is endemic to the south-west of Western Australia.

The sepals are white, 6.5–10 mm (0.26–0.39 in) long, fused for less than half their length, and there are no petals.

[2][3][4] This species was first formally described in 1852 by Nikolai Turczaninow who gave it the name Sorotes rosmarinifolia in Bulletin de la Société Impériale des Naturalistes de Moscou from specimens collected by James Drummond.

[7] This lasiopetalum grows in sandy and gravelly soils in the Avon Wheatbelt, Esperance Plains, Hampton and Mallee biogeographic regions of south-western Western Australia.

[2] Lasiopetalum rosmarinifolium is listed as "not threatened" by the Western Australian Government Department of Biodiversity, Conservation and Attractions.