Province: Arkhangai Province
Centre of sum: Undur-Ulaan, 122 km located from Tsetserleg.
Population: 5'798
Area: 4'000 km2

Undur-Ulaan is a sum (district) of Arkhangai Province in central Mongolia. Founded in 1923. Administrative and territories of Ondor-Ulaan soum  and soum center called Teel. It is 122 km from the aimag center and 560 km from the capital Ulaanbaatar.

The soum has a total population of 5798 and has 1501 households in 2008, with a total of 233578 livestock. It has a territory of 4000 km2. Borders with Ikhtamir, Chuluut, Khangai, Tariat, Jargalant and Erdenemandal soums.

Undur-Ulaan sum is located:

  • 599 km from Ulaanbaatar,
  • 122 km from the aimag center.