Bleiburg is a small city in the state of Carinthia, Austria, south-east of Klagenfurt, in the district of Völkermarkt , near the Slovenian border. It is located approximately 479m above sea level.

According to the census of 2001, Bleiburg has approximately 4121 inhabitants. The municipality of Bleiburg extends to 69.70 square kilometers. It is an old border town located in the Feistritz valley near the Hochpetzen mountain in the Karavanke group.

Bleiburg is home to a district court, military barracks and to the local productive and services industry. The name of Bleiburg, literally meaning "Lead Castle", can be attributed to the lead mining operations in the Petzen mountain. The oldest surviving document mentioning the town is dated to 1228. Bleiburg was elevated to the status of a city in 1370. The annual Wiesenmarkt (meadow market) has taken place every year at least since 1428 on September 1.

Between 1918 and 1920, Bleiburg was occupied by Yugoslav troops, but, in spite of the sizeable Slovenian minority in the surrounding villages, remained with Austria.

In May 1945, Bleiburg was the initial location of the so-called Bleiburg massacre, in the course of which Yugoslav partisans killed thousands of Croatian Ustashe and their supporters. In early September of 2004, the Austrian media reported that the Croatian government had decided to purchase a plot of land near Bleiburg in order to erect a monument to commemorate the massacre, which sparked some minor political controversy in Austria.