Senegambia was a loose confederation between the small West African country of Senegal and its smaller neighbor The Gambia (which is surrounded by Senegal, except for an outlet to the sea), which existed from February 1, 1982 to September 30, 1989 following an agreement between the two countries signed on December 12, 1981. The federation was intended to promote cooperation between the two countries, but was dissolved by Senegal when Gambia refused to move closer toward union.

The name also refers to the geographic region around the two countries, covering the watershed of the Senegal River and Gambia River.

See also Senegambia and Niger, a short-lived administrative unit of French West Africa that existed during the 1900s.