Abstract: On the basis of the remote sensing data products of MODIS surface temperature, surface reflection, vegetation index during 2000—2020 and land use data in 2000,2005,2010 and 2020 in Xinjiang area, as well as Google Earth Engine（GEE） remote sensing cloud platform and remote sensing ecological index（RSEI） model, the change process of land use and the ecological environment quality reflected by RSEI and the impact of land use changes on the ecological environment quality were analyzed, in order to provide a reference for coordinating human activities and ecological environmental protection in the arid regions of Northwest China.The results showed that from 2000 to 2020,the land use in Xinjiang was mainly unused land and grassland, accounting for 59.32% and 28.81% of the total area, respectively.During the study period, the increment of cultivated land area was the largest, reaching 3.09×10~4 km~2;the largest increase in construction land area was 118.18%.The overall quality of ecological environment in Xinjiang in 2000—2020 was low and showed a weak downward trend, which could be divided into rapid decline stage in 2000—2010 and slowed rise stage in 2010—2020,mainly due to the large area of forest land and water converted to cultivated land in the previous period.The improvement area of ecological environment quality in Xinjiang was mainly distributed in the economic belt of the northern slope of Tianshan Mountains, and the decline area was mainly distributed in the southern part of Taklimakan Desert, Junggar Basin and eastern Xinjiang.Land use change in Xinjiang had a significant impact on the ecological environment quality, which was mainly manifested in the increase of cultivated land area, which promoted the improvement of ecological environment quality, while the increase of unused land and construction land lead to the decline of ecological environment quality.Studies suggested that the increase of cultivated land in Xinjiang could effectively promote the improvement of ecological environment quality, but the unused land should be selected for the development of cultivated land, and the development behavior of cultivated land that occupies water body and woodland should be strictly limited.