Dachang Hui Autonomous County (; Xiao'erjing: <big></big>) is a Hui autonomous county of Hebei province. It is under the administration of Langfang prefecture-level city, and was established in 1955. The Hui Muslim county of Dachang was subjected to slaughter by the Japanese in the Second Sino-Japanese War.
Together with Sanhe City, and Xianghe County, it forms the , an exclave of Hebei province surrounded by the municipalities of Beijing and Tianjin, and itself borders Beijing to the west.
A Dachang Hui Imam, Ma Zhenwu, wrote a Qur'an translation into Chinese including Chinese characters and Xiao'erjing.
The county spans an area of , and has a population of about 171,366 people as of 2020.
The county administers one subdistrict and five towns. The county also administers the Hebei Dachang High-tech Industrial Development Zone, which serves as a township-level division. These township-level divisions then administer 16 residential communities, and 105 administrative villages.
Dachang's sole subdistrict is .
Dachang's five towns are , , , Shaofu, and Chenfu.
The county is bounded by the Chaobai River, across from which is Tongzhou District in Beijing.
Dachang's county center lies from Tiananmen Square, and from the center of Tianjin.
34.2% of the county is forested.
As of 2019, Dachang is home to about 27,400 Hui people, comprising approximately 20.45% of the county's population.
As of 2019, Dachang's gross domestic product totaled ÃÂ¥16.48 billion. The county's urban residents have an annual per capita disposable income of ÃÂ¥45,044, and the county's rural residents have an annual per capita disposable income of ÃÂ¥18,418.
A number of expressways pass through the county, including the Jingping Expressway, the Jingqin Expressway, the BeijingâÂÂHarbin Expressway, and the G95 Capital Area Loop Expressway.
Five passenger bus lines link Dachang to Beijing.
The BeijingâÂÂTangshan intercity railway is planned to run through the county, but is still under construction as of 2021.