Deep storage irrigation can give full play to the role of soil reservoir, it can also turn the farmland into a groundwater recharge area to increase the utilization of rainfall resources. Here, Xiaoyan 22 was used as the test variety, five deep water storage depths of 80 cm (D80), 120 cm (D120), 140 cm (D140), 160 cm (D160) and 180 cm (D180) were set up and rainfed (CK) was used as the control to analyze the effects of different treatments on dry matter accumulation distribution, yield and grain filling process of winter wheat. The results showed that the treatments increased the yield by 8.9% (D80), 24.7% (D120), 31.0% (D140), 17.9% (D160) and 9.9% (D180), respectively, compared with CK. Moreover, deep storage irrigation increased the distribution and proportion of seeds in dry matter, among which the proportion of seeds in D140 increased by 2.46% compared with CK. The Logistic equation was suitable for the fitting of the grain filling process of winter wheat at different depths of deep water storage, and the coefficients of determination of the fitted equations were all greater than 0.99. In addition, the deep water storage treatments increased the average filling rate and extended the maximum filling rate by 1.65-3.32 d compared with the control. Therefore, deep storage irrigation has a positive effect on grain filling and yield composition of winter wheat. This study can provide a reference for the fulfillment of making full use of rainfall resources to improve groundwater environment and the achievement of high crop yield.