Abstract: The winter wheat ‘Yujiao 5’ was used to study the effects of irrigation times, nitrogen levels and ratios of base and topdressing N fertilizer on leaf area index and grain yield in a split plot design, with three irrigation times (W1: irrigation before sowing, W2: irrigation before sowing and at jointing stage, W3: irrigation before sowing, at jointing stage and at grain filling stages) being in the main plot, five nitrogen levels (N0: 0 kg/hm², N1: 120 kg/hm², N2: 180 kg/hm², N3: 240 kg/hm², N4: 300 kg/hm²) being in the split-plot and two ratios of base and topdressing (R1: the 3:7 ratio at base and topdressing N fertilizer, R2: the 5:5 ratio at base and topdressing N fertilizer) being in the re-split-plot. The results showed that, three factors significantly affected leaf area index, grain yield and yield components, respectively. There was a positive linear correlation between LAI and nitrogen application rate under W1 treatment. There were significant conics relations between LAI of jointing stage, spiking stage, heading stage in W2 and W3 treatments, and the LAI of N3R2 were the highest. There were highly significant conics relations between grain yield, spike number, kernel number per spike and nitrogen application rate under three irrigation treatments, respectively. Between 1000 kernel weight and nitrogen levels, there was a highly negative linear correlation. In the 27 treatments of irrigation and fertilizer interaction, grain yield (8609.60 kg/hm²), spike number (688.2 thousand plants/hm²) and kernel number per spike (37.9 grains) reached the highest value at W3N3R2, and grain yield of W3N3R2 increased by 144.8% compared to the W1N0 (3517.5 kg/hm²). In conclusion, owing to insufficient rainfall at the late stage of winter wheat in eastern of Henan, the irrigation-saving space was relatively small, but the nitrogen-saving space is relatively large.