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By using the electric rainproof shed at Gucheng Station in Hebei Province, which is located in the littlerainfall and arid regions of the main winter wheat production region of North China, natural precipitation is covered and irrigation is artificially controlled to form soil waterlogging, high humidity, drought, and control. The grain filling process, aboveground biomass, and yield components of winter wheat are measured after flowering. The stress effects of soil waterlogging on the grain filling rate and yield of winter wheat are analysed without the influence of rain and lowtemperature stress. The results show that the grain filling rate of winter wheat decreases and the duration of grain filling days shortens with the decrease of soil water; drought and waterlogging stress affect the dry matter distribution among organs and the sourcesink matching relationship of grain filling in winter wheat. With the decrease of soil water content, the dry matter distribution in the ear decreases, and the stem and leaf weight increases, that is, the biological yield (straw) increases, and the economic yield (grain) decreases. Under the condition of sufficient soil water, the photosynthetic efficiency of green organs such as leaves is high, the transport of photosynthetic products is dominant, and the dry matter of preanthesis vegetative organs has a small contribution rate to the formation and transport of grains; drought stress significantly weakens the photosynthetic capacity of leaves, reduces photosynthetic products and reduces dry matter transport, but the contribution rate of dry matter storage in preanthesis vegetative organs increases. Drought stress affects photosynthesis, grain filling, dry matter accumulation, transport, and distribution of winter wheat plants; during the grain filling period, high soil moisture has a yieldincreasing effect, with a theoretical yield increase of 5.87%. Soil waterlogging shows a decrease in yield, with a theoretical yield decrease of 1.50%; the harvest indices of high humidity and waterlogging are slightly higher than the control 0.5226. Under drought stress, the harvest index significantly decreases, with moderate drought and severe drought being which is 0.1130 to 0.1633 lower than the control. The results show that irrigation in the northern arid region can relieve the stress of climate drought on crop water demand, and when the good weather is full of sunshine, and the daily temperature range is large, the warm and hot conditions are more suitable, and the crop yield and quality are improved. Soil moisture is the key limiting factor affecting the potential of light and temperature production and the increase of yield per unit area of winter wheat in the northern region. The results of this study have certain reference significance for coping with the impact of extreme precipitation events caused by climate change on agricultural production, especially for scientific assessment of the impact of drought and flood disasters on crops in northern arid regions.