Nithsdale was a district council area which existed from 1975 to 1996. It was one of four district councils that delivered a range of local level services within the wider area of the region of Dumfries & Galloway, which over this period was one of the 12 regions into which Scotland was divided.
Nithsdale was formed by joining together the western half of the traditional county of Dumfriesshire with the eastern parts of the traditional county of Kirkcudbrightshire. The main settlements were Dumfries, Moniaive, Thornhill and Sanquhar. It was bordered on the west by Stewartry and on the east by Annandale & Eskdale, both also districts of Dumfries & Galloway. It was bordered on the north by Cumnock & Doon Valley and Clydesdale, both district in Strathclyde Region.
When regions disappeared from the scene in the 1996 reorganisation, the area of Nithsdale became part of the unitary council area of Dumfries & Galloway. For administrative purposes, Dumfries & Galloway is divided by the council into four management areas. These use the names and follow the boundaries of the earlier districts, so the area of Nithsdale District now forms the Nithsdale management area of Dumfries & Galloway.