Sunan Yugur Autonomous County is an autonomous county under the administration of the prefecture-level city of Zhangye, Gansu Province, China, bordering Qinghai province to the south. It is home to the majority of the Yugur ethnic group. The seat of government is in the town of Hongwansi (红湾寺镇).

Zhangye, formerly romanized as Changyeh or known as Kanchow, is a prefecture-level city in central Gansu Province in the People's Republic of China. It borders Inner Mongolia on the north and Qinghai on the south. Its central district is Ganzhou, formerly a city of the Western Xia and one of the most important outposts of western China.