Yi County or Yixian (simplified Chinese: 黟县; traditional Chinese: 黟縣; pinyin: Yī Xiàn) is a county in the southeast of Anhui Province, China, under the jurisdiction of Huangshan City.

and an area of 847 square kilometres (327 sq mi).

The government of Yi County is located in Biyang Town.

The villages of Xidi and Hongcun in Yi County are part of the World Heritage Sites.

During the 16th century, Yi County flourished, and thousands of buildings in the style of Ming Dynasty were built.