Abstract: The field water use efficiency is a key indicator for the water-saving agriculture research.It was divided into three aspects: irrigation water use coefficient,rain water use coefficient,and crop water use efficiency in this paper.These important indicators and calculating methods were respectively analyzed to set up an indicator system of the water use efficiency.The relevant regulating measurements for improving irrigation water use coefficient,rain water use coefficient,and crop water use efficiency were brought forward in order to realize efficient water use in the whole field ecosystem,which would provide scientific instruction for high efficient and sustainable use of agricultural water resources.

Key words: Water use efficiency, Water use efficiency, Indicator system, Regulating measurements