The NDV I of Ejina Oasis was calculated based on the data derived from Landsat TM /ETM + images in 1996, 2000, 2002 and 2006, and in light ofNDV I’s value the land coverwas divided into four types: the bare land, the sparse vegetation area, the lower vegetation area and the dense vegetation area. Through the comparison of the different grade vegetation area change before and afterwater devision, the restoring effect of the vegetation in Ejina Oasis can be found out, and this can supp ly the scientific foundation for the Heihe water - division p lan of the next step. The monitoring results show that the ecological environment of Ejina Oasis kep t deteriorating before 2002, but after seven - yearwater division from upper andmiddle reaches of Heihe River, the environment deterioratingwas alleviated and vegetation was restoring stage by stage.