The Muzart River (Chinese: 木扎尔特河) or Muzat River (Chinese: 木扎提河; Uyghur: مۇزات دەرياسى, ULY: Muzat Deryasi) is a river in Aksu Prefecture of Xinjiang Uyghur Autonomous Region, People's Republic of China, a left tributary of the Tarim River. An early 20th-century source also gives an alternative name for this river, Shāh-Yār-Daryā. Shāh-Yār-Daryā (شاهیاردریا) is a Persian word meaning 'The King's aide River.'
The Muzart River starts in the Muzart Glacier (木扎尔特冰川) in the Tian Shan Mountains, not too far from the Khan Tengri Peak, and flows toward the southeast and east through Baicheng County, in the valley between the main range of the Tian Shan and the Queletage Mountains (却勒塔格山) to the south. Most of Baicheng County's population lives in the valley irrigated by this river.
As the river flows east, toward Kucha, it crosses the Queletage Range in a steep valley. Cut into the northern walls of the valley are 230 caves and grottos, forming the Kizil Caves archaeological site.
The river has been dammed at Chinese: 克孜尔水库; pinyin: Kèzī'ěr shuǐkù). With the surface area of , the reservoir has been described as "the largest swimming pool" in southern Xinjiang. However, its construction may have destroyed the possibility of future archaeological excavations for the area., a short distance upstream of the Kizil site, forming a large man-made lake known as the Kizil Reservoir (
Farther east the river enters a wide plain, where most of its water is taken into irrigation channels supporting the agriculture of the Kuqa, Toksu, and Xayar Counties. Theoretically, the Muzart River is considered a left tributary of the Tarim River, but in practice its waters flow all the way to the Tarim only during the spring-summer flood season.
- Both spellings 木扎尔特河 along the upper course of the river and 木扎提河 along the lower course appear on the same map: Map 16-17 (Aksu Prefecture) in the Atlas of Xinjiang Uyghur Autonomous Region (Series: Road Atlases of China's Provinces, by Xingqiu Publishers (中国分省公路丛书.新疆维吾尔自治区/星球地图出版社编), 2008, ISBN 978-7-80212-469-1)
- "Tarim", in Barthold, W (1993), "Tarim", in Houtsma, Martijn Theodoor; Arnold, T W (eds.), E.J. Brill's first encyclopaedia of Islam, 1913-1936, Volume 1, BRILL, p. 673, ISBN 90-04-09796-1
- Hydrologist consider it part of the "Pobeda - Khan-Tengri glacier massif" (Aizen & Aizen (1998))
- "Kezil Thousand-Buddha Grottoes". xinjiang.gov. Archived from the original on 2007-09-30. Retrieved 2007-08-05.
- "Xinjiang". china heritage quarterly. Retrieved 2007-08-05.
- Vladimir B. Aizen and Elena M. Aizen (1998), Estimation of glacial runoff to the Tarim River, central Tien Shan. In: Hydrology, Water Resources and Ecology in Headwaters