Field experiments were conducted on the effects of nitrogen and phosphorus fertilization on photosynthetic characteristics,dry matter accumulation,and grain yield and water use of winter wheat on the loess tableland of China.Compared with control treatments,leaf area index and photosynthetic rate increased significantly,grain yield increased by 47.6% and water use efficiency increased by 24.6%,averagely under nitrogen and phosphorus fertilization.The effects of fertilization on dry matter accumulation,yield and water use efficiency was as high nitrogen with high phosphorus > high nitrogen with low phosphorus > low nitrogen with low phosphorus > low nitrogen with high phosphorus.The results of variance analysis showed that nitrogen fertilization occupy the main influence while phosphorus fertilization has no impact on winter wheat yield and water use.No interaction between nitrogen and phosphorus fertilization was found.