Weichang is a Manchu and Mongol Autonomous County in far northeastern Hebei province, China. It is administered by Chengde City and is the northernmost county in Hebei, bordering Inner Mongolia to the north.
With an area of 9,058 square kilometres, Weichang is the largest county in Hebei by area. Its mountainous terrain means it is relatively sparsely populated; as of 2020 its population was 423,676.
As an autonomous county, it is designated for the Manchu and Mongol ethnic groups, reflecting the demographic character of this part of northern Hebei near the Inner Mongolian border.