Abstract: Medicago sativa,Zoysia japonica,Carex leucochlora,and Bromus inermis were used as experimental materials, ecological restoration of degraded vegetation was restored by artificial grassland constructing.The effects of different grassland cover on soil evapotranspiration and the main mechanism for water absorption of vegetation were studied by monitoring vegetation NDVI,root volume, water moisture content and soil evapotranspiration real-timely, in order to provide reference for suitable grasses selected of ecological restoration in North of China.The results showed that vegetation biomass increased quickly after all four types of ecological restoration grass were constructed, and soil evapotranspiration reduced obviously in non-growing season.But soil evapotranspiration increased greatly during growing season with vegetation biomass and water absorbed in the soil increasing.Then the peak values of monthly evapotranspiration of different grasslands were Carex leucochlora（112.65 mm）＞Zoysia japonica（107.42 mm）＞Medicago sativa（98.19 mm）＞Bromus inermis（86.69 mm）.Moreover, it was every important for root volume and distribution on soil moisture absorbed.The capacity of water absorption for vegetation was stronger when root volume was greater and root distribution was more concentrated.In the experiment, the main space areas of Carex leucochlora and Zoysia japonica absorbing soil moisture were all 0-20 cm layer of soil, and those of Medicago sativa and Bromus inermis were all 20-40 cm layer of soil.In conclusion, grasses with more capacity of soil and water conservation and less soil moisture absorption should be selected during ecological restoration as far as possible.Bromus inermis was selected firstly, and then, Medicago sativa in the experiment.