The Mariamo or Marri ammu are an indigenous Australian people of the Northern Territory.
The ethnonym Mariamo/Marri Ammu signifies 'plains language'.
The Mariamo tribal lands covered some 100 square miles (260 km2) of swampland south of Mount Greenwood. Their status as an in independent tribe has been maintained by both W. E. H. Stanner and Norman Tindale.
- Green, Ian (September 1989). Marrithiyel, a language of the Daly River region of Australia's Northern Territory (PDF). ANU PhD.
- Tindale, Norman Barnett (1974). "Mariamo (NT)". Aboriginal Tribes of Australia: Their Terrain, Environmental Controls, Distribution, Limits, and Proper Names. Australian National University Press. ISBN 978-0-708-10741-6.