As a hidden water source, groundwater plays the role of important water resources reserve under extreme arid conditions. In recent years, extreme drought events have occurred frequently in the Poyang Lake Basin. To explore the potential storage of groundwater in the Poyang Lake Basin spatially, the groundwater potential area was identified and mapped by the geographic information system (GIS) and the analytic hierarchy process (AHP). A total of 11 influencing factors were selected to characterize the groundwater potential, including lithology, geomorphology, soil type, land use/land cover (LULC), drainage density, curvature, roughness, topographic wetness index, topographic position index, annual precipitation, and slope. The results showed that the combined weight of lithology, geomorphology, soil type, and LULC influencing on groundwater potential reached 0.5. The areas with excellent, good, moderate, poor, and very poor groundwater potential in the Poyang Lake Basin accounted for 12.1%, 26.0%, 34.2%, 18.7%, and 9.0%, respectively, with good and excellent groundwater potential areas mainly distributing in the bottomland of the Poyang Lake area and the river floodplain. According to the validation results, the IAUC value of the ROC curve was 0.755, indicating an excellent prediction performance and reliable potential zoning results. The results clarified the overall groundwater potential of the Poyang Lake Basin, which can provide a reference for the selection of groundwater sources and the regulation of groundwater resources in drought period. This study enriched the theoretical framework and practical application of groundwater research in the Poyang Lake Basin.