Gannan Tibetan Autonomous Prefecture (Chinese: 甘南藏族自治州; pinyin: Gānnán Zàngzú Zìzhìzhōu; Tibetan: ཀན་ལྷོ་བོད་རིགས་རང་སྐྱོང་ཁུལ་, Wylie: Kan-lho Bod-rigs rang-skyong-khul, ZYPY: Gainlho Poirig Ranggyong Kü) is an autonomous prefecture in southern Gansu Province, China, bordering Linxia to the north, Dingxi to the northeast, Longnan to the east and Aba (Sichuan province) to the south.

It includes Xiahe and the Labrang Monastery, Luqu, Maqu and other mostly Tibetan towns and villages.

Gannan has an area of 40,898 km2 (15,791 sq mi) and its capital is Hezuo city (Zoi).

In the first year of the proclamation of Gannan Autonomous District, the district-seat was at the Labrang Town of Sangqu.

The climate is characterised by mild, rainy summers and frigid, but dry and sunny, winters.