Abstract: Abstract: Reducing the loss of irrigation water and increasing water use efficiency (WUE) are important problems needed to be solved in current wheat production. Micro-irrigation can realize a small amount of irrigation for many times and the integration of water and fertilizer. It has been applied in wheat production in recent years. However, the effect of micro-sprinkling times and nitrogen application rate on yield formation and water utilization in winter wheat is poorly understood. In this study, field experiments were conducted from October 2012 to June 2014 at the Wuqiao Experimental Station of China Agricultural University in Cangzhou, Heibei Province (37°41' N, 116°37' E). In 2012-2013, micro-sprinkling 2 times (S2, 750 m3/hm2 irrigation water applied at jointing and anthesis, respectively), 3 times (S3-1, 450, 300 and 750 m3/hm2 irrigation water applied at jointing, booting and anthesis, respectively; S3-2, 750, 450 and 300 m3/hm2 irrigation water applied jointing, anthesis and grain filling, respectively; S3-3, 600, 600 and 300 m3/hm2 irrigation water applied at jointing, anthesis and grain filling, respectively; S3-4, 450, 750 and 300 m3/hm2 irrigation water applied at jointing, anthesis and grain filling, respectively), 4 times (S4, 450, 300, 450 and 300 m3/hm2 irrigation water applied at jointing, booting, anthesis and grain filling, respectively), and flooding (CK, 750 m3/hm2 irrigation water applied at jointing and anthesis, respectively) were designed to preliminarily reveal the effect of micro-sprinkling frequency on grain yield and WUE in winter wheat and select the optimal model for micro-sprinkling 3 times. Results showed that S2 had similar grain yield to CK; S3-3 and S3-4 with the higher ratio of irrigation after anthesis increased thousand grain weight and harvest index and finally improved grain yield, compared with S2; there was no significant difference (P>0.05) in grain yield between S4 and S3-4. So, S3-4 was the optimal model for micro-sprinkling three times. In 2013-2014, 3 micro-sprinkling treatments including S2, S3 (that was S3-4 in 2012-2013) and S4 as well as 3 nitrogen treatments including N1 (45 kg/hm2), N2 (90 kg/hm2) and N3 (135 kg/hm2) were designed to clarify the effect of water-nitrogen coupling on yield formation and water utilization in winter wheat. Result showed that grain yield was higher in N2 than in N1 treatment under S3 condition; however, there was no significant difference (P>0.05) in grain yield among nitrogen treatments under S2 and S4 conditions. The grain yield of S3 and S4 was higher 13.1% to 18.9% than that of S2 under N1 and N2 conditions; however, there was no significant difference (P>0.05) in grain yield among micro-sprinkling times under N3 condition. Nitrogen application rate had no significant effect (P>0.05) on WUE under the same micro-sprinkling time; however, micro-sprinkling time had significant effect (P<0.05) on WUE under the same nitrogen application rate, it in S3 and S4 was 10.5% to 27.8% higher than in S2, and the higher increase occurred in S4. Increasing micro-sprinkling times improved the leaf area index at anthesis and late grain filling stage, delayed leaf senescence, increased the dry matter accumulation after anthesis and thousand grains weight, and finally increased grain yield. Increasing micro-sprinkling times reduced the total water consumption and the proportion of water consumption before anthesis, but increased the proportion of water consumption after anthesis. Appropriately increasing nitrogen application rate (N2) can further increase the dry matter accumulation and the proportion of water consumption after anthesis. Comprehensively, 4 times of micro-sprinkling under the total irrigation rate of 1500 m3/hm2 with suitable nitrogen fertilizer rate of 90 kg/hm2 in spring could realize high yield and high water use efficiency.