Tanchang (Chinese: 宕昌; pinyin: Tànchāng[1]), also pronounced Dàngchāng, is a county in the south of Gansu province, China.

It is the westernmost county-level division of the prefecture-level city of Longnan.

[2] During the 4th-5th century, the region was ruled by the Dangchang Kingdom.

Then as part of the Western Xia, Tanchang was inhabited by Qiangics.

This Gansu location article is a stub.