Ziyun is a county in the southwest of Guizhou province, China, formally known as Ziyun Miao and Buyei Autonomous County. It is under the administration of the prefecture-level city of Anshun.
Its designation as an autonomous county reflects the presence of the Miao and Buyei ethnic groups, for whom the area is named. Such autonomous counties in China are administrative units in which one or more designated ethnic minorities exercise a degree of local self-government, particularly in cultural and demographic affairs.
Ziyun lies in Guizhou, a mountainous southwestern province, and falls within the jurisdiction of Anshun rather than being an independent city. The county seat and surrounding settlements form part of Anshun's administrative territory.