The Moonie River (Mooni River) is a river in Shire of Balonne, Queensland and Walgett Shire, New South Wales, both in Australia. It is a perennial river of the Barwon catchment within the Murray–Darling basin.
The rivers rises south west of Dalby, near Braemar State Forest, south-east of Tara in Queensland, and flows generally to the south-west, joined by thirteen minor tributaries, before reaching its confluence with the Barwon River, before Mogil Mogil farm, north of the village of Collarenebri, New South Wales; descending 198 metres over its 542-kilometre course. The catchment area has no major towns and is extremely flat. The Moonie River is impounded by Thallon Weir, with a capacity of 185 megalitres.
The river flows through the towns of the Nindigully, Flinton and just to the west of Thallon. Both the Moonie Highway and Carnarvon Highway cross the river. In New South Wales, only one public road crosses the river : Gundabloui Road crosses the river near Goondoobluie farm in Collarenbri, about 50 km north of the village.
