Esk River, a perennial stream^[1] that is part of the Clarence River catchment, is located in the Northern Rivers region of New South Wales, Australia.

Esk River rises below Richmond Range, southeast of Tabbimoble, and flows generally to south through Bundjalung National Park towards its confluence with the northern arm of the Clarence River, northwest of the coastal fishing village of Iluka.^[3] The river descends 28 metres (92 ft) over its 25 kilometres (16 mi) course.^[2]

The river is an increasingly popular kayak fishing location that is home to a variety of fish species such as yellowfin bream, dusky flathead and sand whiting in its lower brackish areas and has a good population of Australian bass^[4] in its fresh water reaches. The Esk River is considered the largest untouched coastal river system on the New South Wales North Coast.^[5]

• List of rivers of Australia
• List of rivers of New South Wales (A–K)
• Rivers of New South Wales