[Objective] To analyze the dynamic characteristics of ecological environment quality in Wujiang River basin of Guizhou Province in oreder to provide reference for ecological sustainable development in mountainous basins and ecological civilization construction in the water environment of Yangtze River basin.[Methods] Landsat in 1990, 2000 and 2015 and ASTER GDEM data were used to extract the basic data of vegetation coverage, soil index and soil moisture in Wujiang River basin of Guizhou Province. The weight of each index was determined by expert consultation method. The spatial and temporal changes of ecological environment quality in Wujiang River basin of Guizhou Province were analyzed by comprehensive index evaluation model.[Results] ① During the period from 1990 to 2015, the qualities of ecological environment in Wujiang River basin of Guizhou Province were mainly in "excellent" and "good" levels, accounting for more than 65%. The overall ecological environment quality was showed an upward trend. ② The data show that the spatial differences of ecological environment quality in Wujiang River basin of Guizhou Province were gradually increased, and the ecological environment improvement areas were mainly distributed in the lower reaches of Wujiang River. The degraded areas of ecological environment were mainly concentrated in the upper and middle reaches of Wujiang River. The quality of ecological environment showed that the downstream was better than the middle and upper reaches. ③ The quality of ecological environment in the study area was greatly affected by the level of urbanization, and the ecological environment quality of the main urban areas in the study area decreased significantly during the past 25 years, which was mainly affected by the increase of the built-up area.[Conclusion] The high-precision and long long-term evaluation of ecological environment quality can well reflect the changing characteristics of regional ecological environment quality change. In the future, we should further strengthen the ecological environment management in the middle and upper reaches of the Wujiang River basin in Guizhou Province, with particular emphasis on guiding the coordinated development of the urbanization process and ecological environment in the cities and counties in the study area.