Abstract: In the context of climate change, seasonal drought and wetness have a significant impact on soil NO3--N leaching. Based on precipitation data from 1960 to 2019, this paper extracts meteorological data from decennial drought, decennial wetness and nearest average precipitation in each season, combining into 31 precipitation scenarios, and uses DNDC model to simulate NO3--N leaching flux in different scenarios, the effects of seasonal wet and dry climate on soil NO3--N leaching were explored. The results showed that the more wet seasons, the larger NO3--N leaching flux, and vice versa. The NO3--N leaching is more likely to occur in the rainy season, the rainy period after fertilization or drought. Drought in spring and autumn will cause a significant reduction in NO3--N leaching flux by 83.9% and 63.4%, respectively; while when rainfall occurs in subsequent seasons of the drought in autumn or winter, the NO3--N leaching flux increases significantly. Wet spring leads to a significant increase in NO3--N flux, with an increase of about 50.5%. However, wet autumn has no obvious effect on NO3--N leaching flux. Under the seasonal drought scenarios, NO3--N leaching performs a lagging effect, which poses a significant impact on the subsequent season, and ends in the coming summer; under the seasonal wetness scenarios, NO3--N leaching performs an advancing effect, but it has a small effect on the subsequent season, and ends in the following autumn. This study will be benefit for the risk assessment of non-point source nitrogen loss and the precise agricultural management under the background of climate change.