Ölgii (Oirat: Өлгий [ølʲˈɟiː]; Kazakh: Өлке / Ölke [ɵlʲˈcʰe]) is the capital of the Bayan-Ölgii Aimag (province) of Mongolia, located in the extreme west of the country on the banks of the Khovd River.

Mongolia initially tried to suppress Kazakh language and culture before creating Bayan-Ölgii Aimag in 1939, with Ölgii as the seat of government.

Ölgii developed less than the rest of Mongolia and was not connected by railroad or paved road due to its isolated location and lack of mineral resources.

After the Mongolian democratic revolution in 1991 and the breakup of the Soviet Union, 25% of the population moved to newly independent Kazakhstan.

[citation needed] The Bayan-Ölgii Province longwave radio broadcast mast is located in Ölgii, and is Mongolia's tallest structure at 352.5 metres.

Ölgii experiences a subarctic-influenced desert climate (Köppen BWk, Trewartha BWlc) with long, very dry, very cold winters and short, mild to warm summers.

The government of Mongolia plans to pave the Tsaagannuur to Ulaanbaatar route through Ölgii, Khovd, Govi-Altai, and Övörkhangai Provinces by 2015.