Context: Spatiotemporal variability in precipitation significantly impacts agricultural production in rainfed areas of the Loess Plateau; however, the adaptive mechanisms of winter wheat and nutrient utilization in response to precipitation distribution and amount remain unclear. Objective: This study aims to reveal the effects of precipitation distribution and amount during different growth stages on winter wheat yield, nutrient use efficiency, and nutrient surplus in rainfed areas of the Loess Plateau, and to formulate water and fertilizer management strategies that effectively balance crop nutrient demands and reduce environmental risks. Methods: A field experiment was conducted from 2017 to 2024 across five counties in China's Loess Plateau, including two fertilization regimes: optimized fertilization (OF) and farmers' practices (FP). Different precipitation patterns (HVHR, HVLR, LVHR, and LVLR) were classified based on high/low precipitation during the vegetative growth (VG) and the reproductive growth (RG) stages. Linear regression analysis was used to quantify the relationship between yield and precipitation during the VG and RG stages, thereby determining optimal precipitation thresholds for high yield. Based on these thresholds, optimized water and fertilizer management strategies were developed and then validated through a field trial. Results: Precipitation during the VG and RG stages explained 65% and 35% of yield variation, respectively, with the optimal precipitation thresholds identified as 246-275 mm for the VG stage and 119-127 mm for the RG stage. The HVLR pattern achieved the highest wheat yield by synergistically increasing spike number and 1000kernel weight, whereas fertilization regimes had no significant effect on yield. Compared with FP treatment, OF treatment reduced N and P input by 31% and 40%, respectively, while significantly improving the partial factor productivity of N and P by 27% and 54% across all precipitation patterns. A validated water-fertilizer strategy meeting the optimal precipitation thresholds through supplemental irrigation increased yield by 23.1% under the OF treatment, lowered N and P surpluses to 1.5 and 1.3 kg ha-1, and reduced soil nitrate-N residues to a level below the established safety threshold. Conclusion: Our results demonstrate that the synergistic management of water and fertilizer, guided by precipitation patterns, can simultaneously enhance crop yield and reduce environmental risks in dryland wheat farming systems.