Wetlands are extremely important nitrogen pool on Earth, and are highly sensitive to global changes such as increased atmospheric nitrogen deposition and climate warming. Previous studies on wetland nitrous oxide (N₂O) had large regional imbalance. The responses of wetland N₂O emissions to global changes remain unclear. In this study, we carried out in situ N₂O flux monitoring, and implemented global change experiments in a Carex cinerascens Kukenth. meadow of Lake Poyang to characterize N₂O emission and its response to nitrogen addition and warming. The results showed that the C. cinerascens wetland of Lake Poyang was generally a weak source of N₂O, with an average N₂O flux of (5.77±1.45) μg/(m²·h). Nitrogen addition significantly increased N₂O flux by 2.7 times. There were no significant effects of warming and its interaction with nitrogen addition on N₂O flux. N₂O efflux was mainly regulated by wetland plants, while there was no significant correlation between N₂O flux and abiotic factors such as air temperature, soil temperature and soil moisture. These results provided in-depth understanding of the feedbacks between global changes and N₂O emissions from lake wetlands, and provided support for the assessment of N₂O budget in lake wetlands under the background of global changes. In the future, it is necessary to strengthen the study of multi-factor interactions, and to carry out long-term continuous monitoring, and thus to provide validation data and theoretical basis for elucidating the response mechanism of wetland nitrogen cycle to global changes and developing climate prediction models.