Southern Altai (also known as Oirot, Oyrot, Altai and Altai proper) is a Turkic language spoken in the Altai Republic, a federal subject of Russia located in Southern Siberia on the border with Mongolia and China. The language has some mutual intelligibility with the Northern Altai language, leading to the two being traditionally considered as a single language. According to modern classifications—at least since the middle of the 20th century—they are considered to be two separate languages.^[5]

Written Altai is based on Southern Altai. According to some reports, however, it is rejected by Northern Altai children. Dialects include Altai Proper and Talangit.^[6]

Southern Altai is a member of the Turkic language family. Within this family, there have been various attempts to classify Altai, and not all of them agree as to its position as it has a number of ambiguous characteristics.^[7] Due to certain similarities with Kyrgyz, some scholars group Altai with the Kyrgyz–Kipchak subgroup of the Kypchak languages.^[2][3][8]

Southern Altai is primarily spoken in the Altai Republic, where it has official status alongside Russian.

Southern Altai has 8 vowels, which may be long or short, and 20 consonants, plus marginal consonants that occur only in loan words.^[11]

Southern Altai employs a version of the Cyrillic alphabet with additional characters to represent sounds not found in Russian.^[12]