Abstract: A new species of Advenimus, A. ulungurensis sp. nov., is described based on dental specimens collected from Tertiary beds on the south bank of the Ulungur River in northern Junggar Basin of the Xinjiang Uygur Autonomous Region of China. These specimens represent the first record of ctenodactyloids in Xinjiang. Correlations with distributions of other species of Advenimus indicate diat the bed yielding the Xinjiang fossils is of probably early Eocene in age.