Abstract: Gelmud River Basin is one of the most developed industrial and agriculture areas in Chaidamu basin.In recent years,ecologic environment has deteriorated gradually with the development of basin water resource and unreasonable water use structure.This thesis analyzed the influence of groundwater depth to plant growth from the grow situation of main plants in the basin,and confirmed different groundwater depths,lithology character and plant evaporate strength under different coverage degrees.From the research on basin ecologic water demand,the paper preliminarily estimated on the natural vegetation of inner river and outer river and ecological water demand of east Dabuxun lake,analyzed the influence of water resource development to ecological environment,and provided the theoretical basis for the research on basin water resource development and ecological environmental protection.