Abstract: Variations in basin land surface are influenced by both climate change and human activities, which largely altered the hydrological connectivity of the catchment, leading to many eco-environmental problems to develop. In this paper, we considered the Poyang Lake catchment as the study area, and used the system for automated geoscience analyses (SAGA) combining the topographic wetness index and network index method to perform connectivity analysis. We analyzed the spatial pattern of hydrological connectivity, and revealed the impact of slope change, land uses, and soil types on hydrological connectivity. Additionally, the relationships between hydrological connectivity and soil erosion and flood disaster were explored for the purpose of application. The results found that the hydrological connectivity of the Poyang Lake catchment is generally high in the northern catchment and relatively low in the southern catchment. In general, the Poyang Lake catchment can be divided into three sub-regions, including the strong hydrological connection area around the lake, the medium connectivity area around the river system, and the weak connectivity area in the upstream mountainous catchment. Spatial analysis further showed that NI values in low-lying areas with low slope is generally high, while aera with large fluctuation area NI values is small. That is, topographic factors have an important impact on hydrological connectivity. In terms of different land uses, the hydrological connectivity of shrub and forest is weak, and that of wetland, water body and cultivated land is high. For different soil types, the hydrological connectivity of yellow soil and yellow brown soil is the worst, and that of alluvial soil, water area and paddy soil is better. This is because the dominant role of the catchment topography, but the soil infiltration capacity, water storage and runoff characteristics of the underlying surface may play a combine role in affecting the spatial difference in the hydrological connectivity. Although this study focuses on hydrological connectivity from a macro perspective, it can provide decision-making basis for watershed soil protection, land use planning, and natural disaster response.