Mann River, a perennial stream of the Clarence River catchment, is located in the Northern Rivers district of New South Wales, Australia.

Mann River rises at Llangothlin Lake, on the slopes of the Great Dividing Range, near Ben Lomond and flows generally north north east, east, north east and north, joined by four tributaries including the Nymboida River, Henry River and Yarrow River, before reaching its confluence with the Clarence River, southwest of Baryulgil. The river descends 1,370 metres (4,490 ft) over its 238 kilometres (148 mi) course;^[2] and flows through the Mann River Nature Reserve.^[3][4]

The river is believed to be named in honour of Samuel Furneaux Mann, who held a squatting licence for a short time in the region northwest of Glen Innes^[1] or for Gother Kerr Mann, a prominent settler in the area.^[5] Another name for the river, rarely used now, is Mitchell River,^[6][7][8][9] probably named after Thomas Mitchell.

• Rivers of New South Wales