Bad Bleiberg (Slovene: Plajberk pri Beljaku) is a market town in the district of Villach-Land, in Carinthia, Austria.

Originally a mining area, especially for lead (German: Blei), Bad Bleiberg today due to its hot springs is a spa town.

King Henry II of Germany granted the Carinthian lands around Villach to the newly created Diocese of Bamberg at the Frankfurt synod of 1 November 1007, together with other estates like Griffen or the Canal Valley around Tarvisio.

The mine was first mentioned as Pleyberg in a 1333 deed issued by the Bamberg bishops; it was operated by the Swabian Fugger family from the late 15th century onwards.

When in 1951 a hot spring had flooded an adit, a public bath was established and Bleiberg received the official Bad title of a spa town in 1978.