Scientific research on hydrological drought in lake-floodplains and its impact on hydrological connectivity is of great significance for local water resources management and wetland ecological protection. Based on the reconstructed high spatiotemporal resolution inundation datasets from 2000 to 2023 by applying the ESTARFM model (Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model), hydrological drought and hydrological connectivity in the Poyang Lake were quantitatively characterized by the standardized inundation area index and the geostatistical hydrological connectivity function, and then their evolution characteristics were analyzed. On this basis, the response of hydrological connectivity to hydrological drought was further clarified by using the methods of STL (Seasonal and Trend decomposition using Loess) time series decomposition and multivariate linear fitting function. The results showed that both annual and interannual variations of hydrological drought in Poyang Lake were complicated, with a high frequency of occurrence and an increasing drought tendency. The hydrological connectivity in the north-south direction of the Poyang Lake is stronger than that in the east-west direction. In recent years, the hydrological connectivity of the Poyang Lake has shown a fluctuating downward trend, which is related to the intensity changes of lake hydrological drought. Further quantitative analysis found that with the increase of the degree of hydrological drought, hydrological connectivity in the Poyang Lake showed a decreasing trend. In the east-west direction, the annual average hydrological connectivity of light drought, medium drought, severe drought and extreme drought in the Poyang Lake can decrease by 45.2%, 50.0%, 54.6% and 70.7%, respectively, compared to no drought scenario. Similarly, in the north-south direction, the annual average hydrological connectivity can decrease by 32.1%, 35.6%, 39.0% and 50.7%, respectively. The changes of hydrological connectivity caused by hydrological drought in the Poyang Lake area will further impact affect the growth and distribution of wetland vegetation, and the results of this study provide scientific basis for the management practice of lake ecosystems under extreme water conditions.