Abstract: As the basis for human survival and development，global biodiversity is facing a serious threat，species diversity is the center of biodiversity and the main unit of structure and function，and also is the basis and crucial for regional and global biodiversity conservation. Arid area of the world has a large area，and arid area in Central Asia is one of the key areas for species diversity，fragile ecological environment is strongly influenced by rapid population growth，land use and resource development，and the global change will also bring potential harm to vulnerable species diversity in the arid area，what is an urgent requirement to strengthen international cooperation to conduct research on biodiversity in the arid areas. This paper summarized the information on the basis of existing data on species diversity of Xinjiang and Turkmenistan，and then analyzed their current situation on species diversity，characteristics of rare animals and plants，as well as endangered species and invasive species. The results show as follows：higher plants，mammal and insect species found in Turkmenistan are less than that in Xinjiang，and Xinjiang has a little more in respect of fungi，algae，lichens，reptiles and fish. Turkmenistan's threatened species ratio was increased from 1.4% in 1990 to 3.8% in 2010. The vertebrate species in Xinjiang are only 83 kinds above that of Turkmenistan，while the proportion of threatened vertebrate in Xinjiang is as high as 16.5%，and which is 4.34 times over Turkmenistan，and the situation of animal diversity protection is grim. The threatened vascular plants in Turkmenistan was increased from 1.7% to 6.3%，much higher than in Xinjiang. Vegetation in Turkmenistan degradation seriously，while threatened bird species in Xinjiang of China is more serious，accounts to 75 species in 2010，and account for 16% of total bird species. The total number of two places’ endangered species is up to 133；compared with Turkmenistan，invasion of higher animals in Xinjiang is not optimistic， invasion of higher plants in Turkmenistan and Xinjiang is up to 22%，higher plants invasion is more intensified than that of animals，which is bound up with deliberate introduction．

Key words: Turkmenistan, Xinjiang, species diversity, endangered species, invasive species