Saltwater River (also known as Saltwater Creek) is a former penal colony on the Tasman Peninsula in Tasmania, Australia. It is 23 kilometres (14 mi) from Port Arthur, and 106 kilometres (66 mi) from Hobart. At the 2006 census, Saltwater River had a population of 156.
The Saltwater River area contained two penal settlements. One was an agricultural settlement, which produced vegetables, wheat, and had a piggery. The other was a coal mine, known amongst convicts for its hellish conditions. It is now on the Australian National Heritage List as the Coal Mines Historic Site.
Today, only ruins exist at the site, which include underground cells.
Saltwater River Post Office opened on 1 December 1878 and closed in 1970.