The invention relates to a method for fertilizing winter wheat by the mixed basal application of a nitrogen fertilizer and maize straw. The method comprises the following steps of: (1) crushing summer maize straw in fields, returning to the fields completely, and spraying a nitrogen fertilizer solution on the surface of the crushed maize straw uniformly; (2) performing rotary tillage or ploughing; (3) sowing the winter wheat, and applying a phosphorus fertilizer, a potash fertilizer and a trace element fertilizer in a seed manure application mode; and (4) dressing the nitrogen fertilizer onceat the elongation stage of the winter wheat. According to the method, by a field returning mode of spraying the nitrogen fertilizer on the surface of the maize straw, a carbon nitrogen ratio of the straw is regulated, and the nutritional environment which facilitates the growth of straw decomposition microbes is constructed, so that the growth of the microbes is facilitated, the decomposition speed of the straw is improved, inorganic nitrogen of the fertilizer is converted into organic nitrogen, the loss of the nitrogen fertilizer is reduced, and the fertilizer efficiency of the nitrogen fertilizer is improved; and at the middle and late growth stage of the wheat, the amount of the organic nitrogen released by mineralizing the maize straw through the microbes is gradually increased, so that the growth requirement of the wheat at the middle and late growth stage on a nitrogen element is met.