Abstract: Scientifically evaluating the influences of the extension of water-save technology and the comprehensive reform of water price on the water use intensity is critical to the formation of water-saving policies. Based on a provincial panel data of major wheat, corn, and rice production areas from 2003 to 2016, this paper constructed a theoretical decomposition model of the water use intensity by incorporating technological progress and irrigation water prices to explore the factors influencing the change of the agricultural water use efficiency. Results show that in the sample period, the irrigation water intensity of three crops displayed a steady declining trend (Decline range: corn > wheat > rice). The effect of the irrigation water price on the water use intensity was characterized by dissimilation among crops, which greatly promoted the reduction of the water use intensity of corn. However, there was a kind of inhibitory effect on wheat and rice. The agricultural water use intensity was greatly reduced by agricultural technical innovation and technical efficiency improvement. For the degree of its impact, there was a certain degree of heterogeneity among crops. In addition, there was a strong effect of agricultural technical innovation on the improvement of the water use intensity of corn and rice. However, the contribution of technical efficiency to the reduction of the water use intensity of wheat was the largest. In summary, this paper suggests: to formulate a water price mechanism, to make targeted scientific and technological innovations in the weak links of crop production, and to optimize the level of production management and scale efficiency based on the water use habits of different crops.