Desertification is one of the most serious environment and socio-economic problems in the world and China today. Land of sandy desertification almost covers everywhere in Ejina Banner(a county，Inner M ongolia Autonomous Region. Using remote sensing method can expediently acquire some inf}omation such as desertification status and effect of harnessing desertification. The ecological change situation from 1986 to 2000 in Ejina onsis is researched. The result is as followes(1) Area of water body of lakes on the northern and eastern are distinctly reduced.(2) Area of the oasis is rapidly shrunk. From 1986 to 2000, the area is r,duced 61.48%，average 4.39% annually.(3) condition of oasis quality is declined. The oasis ecological environment trends to be bad.Its main reason is that human activities exc ded the load capacity of natural resources such as wester and land. By means of selfstorative ability of natural vegetation and human scientific conservation,that the oasis,cosystem maintains dynamical balance and the environment remains relatively stable is possible.