The Lambussie Karni District is one of the 261 Metropolitan, Municipal and District Assemblies (MMDAs) in Ghana, and forms part of the 11 of Municipalities and Districts in the Upper West Region.

The District was created from the Jirapa Lambussie District Assembly by the legislative Instrument (LI) 1849 in 2007 and has its administrative capital at Lambussie.  Other major towns in the District include Hamile, Samoa, Billaw, Piina and Karni.

The Lambussie Karni District lies in the north-western corner of the Upper West Region of Ghana.  The location of the District is strategic as its proximity to Burkina Faso could enhance cross border trade and other mutual relationships in terms of exchange of ideas for the development of the District.

The District shares boundaries to the south with Jirapa Municipal Assembly, to the east with Sissala West District, to the west with the Nandom District and to the north with Burkina Faso. The District, therefore, serves as the National Gate way to Burkina Faso.

In terms of size, it covers a total land area of 803 square kilometres.

The population of the District according to 2021 population and housing census stands at 51,118 with 25,060 males and 26,058 females.