Southern Schleswig is a name for the geographical area covering the 30-40 most northern kilometers of Germany where Germany borders to Denmark. Together with Northern Schleswig which is the most southern part of Denmark it constitutes the region Schleswig.

In German the area is simply known as Schleswig whereas in Danish the area is known as Sydslesvig.

Southern Schleswig is only known as a region differentiated from the rest of Schleswig-Holstein by a small amount of its inhabitants, mainly by the members of the Danish minority of Southern Schleswig.

Major cities in the southern part of Schleswig are Flensburg, Rendsburg, the city of Schleswig and Husum.