Abstract: The changes of ecological environment in Ejina oasis have experienced a complicated and very long period.With processes of water resource exploitation and use and man-made oasis construction,the changes of distribution of water resources in time and space,land desertification,salinization of soil,degradation of desert riverbank forest and deteriorate of water quality have become serious.Through a systematic analysis on resources of water,land and vegetation,a assessment was made on environmental capacity of the oasis in accordance with the ecological principles of land exploitation with full of supply of water resources.This paper also made environmental impact assessment related to the exploitation and use of the oasis and put forward the ways of water resource use and eco-economic development in Ejina oasis.