Mori Kazakh Autonomous County is a county within the Xinjiang Uyghur Autonomous Region and is under the administration of the Changji Hui Autonomous Prefecture. It contains an area of 13,510 km<sup>2</sup>. According to the 2002 census, it has a population of 90,000.
People have been active within the county's borders for over 3,000 years. In 60 BC (the second year of the Shenjue era of the Han Dynasty), the Han government established the Protectorate of the Western Regions, governing 36 kingdoms in the Western Regions. Mulei belonged to the Kingdom of Pulei. After unifying the Western Regions, the Tang government established Tingzhou in 640 AD (the fourteenth year of the Zhenguan era), with Pulei County under its jurisdiction. Mulei belonged to Pulei County and was under the jurisdiction of Tingzhou. In 713 AD (the first year of the Kaiyuan era of the Tang Dynasty), the Tang government established the Dushan Garrison in the present-day Mulei County.
In 1917, the Mulei River County was established and belonged to Qitai County. The following year, the construction of Mulei City began. In March 1930, Mulei County was established and separated from Qitai County, and named Mulei River County. In March 1954, Mulei River County was renamed Mulei County. In July of the same year, the Mulei Kazakh Autonomous Region was established. In March 1955, it was renamed Mulei Kazakh Autonomous County. In May 1958, it was transferred to Changji Hui Autonomous Prefecture.
At the end of 2020, according to the data from the Seventh National Population Census, the county's permanent resident population was 67,256.
Mori County is made up of 4 towns, 6 townships, and 1 ethnic township.