Organic fertilization, like using livestock manure, can boost winter wheat yield and water use efficiency in northern China. By combining organic fertilizer with less synthetic nitrogen, farmers can increase grain yield by up to 28%. This method works best when wheat yield is below 4.0 Mg ha–1 and when synthetic nitrogen application is less than 150 kg N ha−1. In regions with low soil organic matter and evapotranspiration levels, organic fertilization is most effective. Overall, using organic fertilizer alongside reduced synthetic nitrogen can help improve sustainable wheat farming in northern China.