Up to now,great progresses in the construction of eco-environment have been made,especially afforestation in the"Three Norths"of North,Northeast and Northwest China.Accord-ing to statistics,up to1997,afforested area of the whole country had reached46.27million ha,among of them30.24million ha were located in the"Three Norths".However,in the process,some problems still exist which need to be solved as soon as possible,in particular,the relative low survival rate and preservation rate which are only25%and13%respectively.The analyses show that scarce rainfall,drought and the shortage of soil moisture are the main reasons for this phenomenon.Therefore,water resources are the cores of the reconstruction of ecosystem in Northwest China.The effective approaches to overcome the shortage of water resources there in-clude interbasin water transfer,effective water management ,resourcelization of rain water,de-veloping water-saving agricultural techniques,popularizing water-saving awareness,etc.