The Ulungur River or Urungu (Mongolian: Өрөнгө гол, Öröngö Gol; Chinese: 乌伦古河 Wūlúngǔ hé), in its upper reaches in Mongolia known as the Bulgan River (Mongolian: Булган гол), is a river of China and Mongolia. It rises in the Altai Mountains in western Mongolia, flows south into China's Xinjiang (Altay Prefecture), where it turns northwest to empty into the Ulungur Lake.