Ürümqi is the capital of the Xinjiang Uyghur Autonomous Region in Northwestern China. With a census population of 4 million in 2020, Ü…Ürümqi is the capital of the Xinjiang Uyghur Autonomous Region in Northwestern China. With a census population of 4 million in 2020, Ürümqi is the second-largest city in China's northwestern interior after Xi'an, as well as the largest in Central Asia in terms of population. Ürümqi has seen significant economic development since the 1990s and currently serves as a regional transport node and a cultural, political and commercial center.