联合国东斯拉夫尼亚、巴拉尼亚与西锡尔米乌姆过渡机构（United Nations Transitional Administration for Eastern Slavonia, Baranja and Western Sirmium, UNTAES）是联合国在克罗地亚战争之后，在1996年到1998年之间，为了使克罗地亚境内塞尔维亚人控制的东斯拉夫尼亚、巴拉尼亚、西斯雷姆地区和平回归克罗地亚所设立的维和任务。

The United Nations Transitional Administration for Eastern Slavonia, Baranja and Western Sirmium (UNTAES) was a UN peacekeeping mission in Eastern Slavonia, Baranja and Western Syrmia in the eastern parts of Croatia between 1996 and 1998, established by the United Nations Security Council Resolution 1037 of January 15, 1996. It is also sometimes known as the United Nations Transitional Authority in Eastern Slavonia, Baranja and Western Sirmium.