Scientific research on hydrological drought in lake-floodplains and its impact on hydrological connectivity is of great significance for the management of local water resources and the protection of wetland ecosystems. This study utilized the ESTARFM model (enhanced spatial and temporal adaptive reflectance fusion model) to reconstruct high spatiotemporal resolution inundation datasets from 2000 to 2023. The resulting datasets were then employed to quantitatively characterize hydrological drought and hydrological connectivity in Lake Poyang. To this end, the standardized inundation area index and the geostatistical hydrological connectivity function were utilized to analyze the evolution characteristics of the aforementioned phenomena. On this basis, the response of hydrological connectivity to hydrological drought was further clarified by employing the methods of STL (seasonal and trend decomposition using Loess) time series decomposition and multivariate linear fitting function. The findings indicated that the hydrological drought in Lake Poyang exhibited both annual and interannual variations, characterized by a high frequency of occurrence and an escalating drought trend. The hydrological connectivity in the north-south direction of the Lake Poyang is stronger than that in the east-west direction. In recent years, the hydrological connectivity of Lake Poyang has exhibited a fluctuating downward trend, which is associated with variations in the intensity of hydrological drought. Subsequent quantitative analysis revealed that with an increase in the degree of hydrological drought, hydrological connectivity in Lake Poyang demonstrated a downward trend. In the east-west direction, the annual average hydrological connectivity of light drought, medium drought, severe drought and extreme drought in the Lake Poyang can decrease by 45.2%, 50.0%, 54.6% and 70.7%, respectively, compared to a no drought scenario. In a similar fashion, in the north-south direction, the annual average hydrological connectivity can decrease by 32.1%, 35.6%, 39.0% and 50.7%, respectively. The alterations to hydrological connectivity occasioned by hydrological drought in the Lake Poyang area will have further consequences for the growth and distribution of wetland vegetation. The results of this study provide a scientific basis for the management of lake ecosystems under extreme water conditions.