Abstract: Methane (CH₄) emissions from floodplain wetlands are of crucial significance and must be meticulously incorporated into global CH₄ budget estimations. CH₄ emissions are sensitive to climate change; however, their responses to extreme drought remain unclear, which limits our understanding of their role in the global carbon budget and climate feedbacks. In this study, CH₄ emissions from two distinct vegetation types (the short wetland Carex community and the tall emergent Triarrhena community) were measured in situ at Poyang Lake, China’s largest floodplain lake, during the autumn-winter growth period of 2022 and the subsequent spring-summer growth period of 2023. We found that the floodplain lake acted as a significant CH₄ source with a mean emission flux of (1.80 ± 1.50) mg/(m²∙h), underscoring the important contribution of the floodplain lake to CH₄ emissions under extreme drought conditions. Importantly, vegetation played a crucial role in sustaining these emissions. The mean CH₄ fluxes of Carex (1.78 ± 1.27) mg/(m²∙h) and Triarrhena (1.82 ± 1.73) mg/(m²∙h) were similar, yet the two vegetation types relied on distinct regulatory mechanisms. While Carex emissions were primarily driven by temperature, Triarrhena emissions were predominantly influenced by above-ground biomass. CH₄ fluxes during the extreme drought year were lower than those in normal hydrological years. However, the altered hydrological rhythm, characterized by earlier exposure in autumn and delayed flooding in spring, prolonged the emission period and offset reductions in CH₄ fluxes during the drought year. Overall, CH₄ emissions remained considerable under extreme drought conditions in Poyang Lake, providing important insights into the impacts of climate extremes on CH₄ dynamics in floodplain wetlands.