In order to explore the feasibility of supplementing soil water and groundwater by using rainfall and flood resources in flood season,the experiment was carried out in maize field plots from June to October 2020,monitoring the characteristics of soil water dynamic changes under one-time deep storage irrigation with different planned water storage depths (T1:H_p=60 cm;T2:H_p=90 cm;T3:H_p=120 cm;T4:H_p=150 cm;T5:H_p=180 cm) and saturated water content as the upper limit of irrigation,and studying the quantitative farmland water dynamics of groundwater replenishment,so as to provide the basis for formulating the deep storage irrigation system for effectively replenishing soil water storage.The results showed that deep storage irrigation could effectively replenish the farmland soil moisture.After 10 days of irrigation,the average water content of 0—200 cm soil layer of each treatment increased by 11.90%~40.85%,and the water content of T5 treatment had the highest water content increase.With the increase of the planned water storage depths,evapotranspiration of summer maize farmland increased first,then decreased,and finally rose to the highest level,and the treatment reached the maximum in the 90 cm planned wetting layer.When the planned water storage depths were 60 cm and 90 cm,the supplementary water was mainly used to recharge shallow soil and farmland evapotranspiration,which was not conducive to soil water storage.When the planned water storage depths were more than 120 cm,the water supply of deep soil by irrigation and rainfall was more than 243.39 mm,accounting for more than 27.29% of the total water supply.In conclusion,deep storage irrigation was an effective irrigation method to replenish soil water,and selecting the planned water storage depths above 120 cm for deep storage irrigation could effectively optimize the water resources allocation and replenish shallow soil water storage and even groundwater.