The Sangjiangyuan National Park, locating in the hinterland of Qinghai-Tibet Plateau, is the most concentrated area of plateau biology diversity. From 2015 to 2017, the faunas and distribution of wide mammals in Sangjiangyuan National Park were recorded in the national park. These 62 species belonged to 8 orders, 19 families, and 44 genera. From the classification system, the species of Carnivora, Rodentia, Artiodactyla were rich, and species of Chiroptera, Primates, Perissodactyla were poor. The mammal fauna feature of Sanjiangyuan National Park is high species diversity, existing many endemic species, key protected species and threatened species, which shows the extremely high conservation value. The results of G-F index showed that the species diversity was high in Sanjiangyuan National Park. A total of 28 species of mammals in the national park were included in key protected wildlife, accounting for 45.16% species distributed: 8 and 14 species were class I and II nationally key protected animals, respectively, and six species were listed in the list of key protected animals of Qinghai Province. And 20 species were classified as threatened (including critically endangered, endangered, vulnerable) category of Red List of China’s Vertebrates, accounting for 32.26% species distributed in Sangjingyuan National Park. 29 species were endemic to China or Qinghai-Tibet Plateau, accounting for 46.77%. The wild animal fauna of Sanjiangyuan National Park belongs to the Palearctic realm Qinghai-Tibet region and a total of 9 geographical distribution

pattern were identified, including 25 species of high alpine types which had great population amount. The results showed that the main species in Sanjiangyuan National Park highly adapted the dry-and-cold weather of the plateau. The results of average faunal resemblance analysis suggested that the Yellow River source park was closely related to Yangtze River source park and Lancang River source park, and the Yangtze River source park was consistently related Lancang River source park. In recent years, the work of mammals conservation in Sanjiangyuan area has achieved good results and has been recognized at home and abroad, and some suggestions for monitoring and protection in the future were put forward according to the current situation of the national park.