It is a rare species and the largest Diuris in Western Australia.

[2][3][4][5] Diuris amplissima was first formally described in 1991 by David Jones from a specimen collected near Moodiarrup, and the description was published in Australian Orchid Review.

[3][6] The specific epithet (amplissima) is a Latin word meaning "largest",[7] referring to the "impressive flowers".

[3] Giant donkey orchid grows in woodland and forest between Porongurup and Capel in the Avon Wheatbelt, Jarrah Forest and Mallee biogeographic regions.

[2][5][8] Diuris amplissima is classified as "not threatened" by the Western Australian Government Department of Biodiversity, Conservation and Attractions.