阿尔巴尤列亚（罗马尼亚语:Alba Iulia、拉丁语: Apulum、德语: Karlsburg/Weißenburg，卡尔茨堡/卡尔斯堡、 匈牙利语: Gyulafehérvár, 土耳其语：Erdel Belgradı）是罗马尼亚的一个城市。阿尔巴尤列亚是阿尔巴县的首府所在地。阿尔巴尤列亚在罗马尼亚和匈牙利两国的历史上都有非常重要的地位。

Alba Iulia (Romanian pronunciation: [ˌalba ˈjuli.a]; German:Karlsburg or Carlsburg, formerly Weißenburg, Hungarian:Gyulafehérvár, Latin:Apulum, Ottoman Turkish: Erdel Belgradı or Belgrad-ı Erdel) is a city located on the Mureş River in Alba County, Transylvania, Romania, with a population of 63,536 as of 2011. Since the High Middle Ages, the city has been the seat of Transylvania's Roman Catholic diocese. Between 1541 and 1690 it was the capital of the Eastern Hungarian Kingdom and the latter Principality of Transylvania. Alba Iulia is historically important for Hungarians, Romanians and Transylvanian Saxons.