The Darling Sedimentary Basin, or simply the Darling Basin, is located in western New South Wales, bordered in the north by the line Broken Hill-Wilcannia -Cobar and stretching southward towards the Murray River. It is an old sedimentary basin dated by Late Cambrian/Silurian to Early Carboniferous. It is an intra-cratonic depositional center, mostly filled with Devonian sedimentary rocks up to 8 km in thickness. It is overlaid by the Eromanga Basin in the north and the Murray Basin in the south. It covers the area on over 100,000 km<sup>2</sup>.
Darling and Murray basins are separated by the Lachlan Fold Belt.
Major troughs and sub-basins include Cobar Basin, Mt Hope Trough, Rast Trough and Melrose Trough.
The Moomba to Sydney Pipeline crosses the area.