Pityrodia byrnesii is a flowering plant in the mint family Lamiaceae and is endemic to Arnhem Land in the Northern Territory.

It is a shrub with hairy, glandular stems, stalkless, flat leaves and fragrant, off-white, bell-like flowers with purple stripes inside the tube.

Pityrodia byrnesii is a shrub which grows to a height of about 1 m (3 ft) and which has its branches densely covered with glands and hairs.

[2][3] Pityrodia byrnesii was first formally described in 1979 by Ahmad Abid Munir from a specimen collected near the East Alligator River crossing in the Northern Territory.

[4] This pityrodia occurs in Arnhem Land, near the East Alligator River, about 10 km (6 mi) south-west of Gunbalanya in the Kakadu National Park.