Abstract: To clarify the spatiotemporal evolution of drought in the Huang-Huai-Hai Plain of China, this study investigated long-term drought dynamics using multi-index comparison and three-dimensional event identification techniques. The research aimed to explore regional drought characteristics and to determine the most suitable drought indicator for this specific plain from 1960 to 2020. Daily meteorological observations from 102 stations and regional soil property data were used to calculate four monthly drought indices: the Palmer drought severity index (PDSI), the self-calibrating palmer drought severity index (scPDSI), the Standardized Precipitation Index (SPI), and the standardized precipitation evapotranspiration index (SPEI). A three-dimensional dynamic drought identification framework was employed to merge spatially contiguous drought grids across successive months, thereby constructing continuous spatiotemporal drought volumes. For each identified event, duration, cumulative severity, mean intensity, maximum affected area, and centroid migration distance were extracted. The performance of the four indices was evaluated by comparing identified events with documented historical drought records and disaster statistics, and the most suitable index was selected for further spatiotemporal analysis. Among the four indices, scPDSI demonstrated the highest applicability for the Huang-Huai-Hai Plain, as it most consistently matched historical drought occurrences and regional hydroclimatic conditions. Over the 61-year period, 89 independent drought events were identified using scPDSI. The longest event persisted for 13 months, and the maximum cumulative severity reached 6.3×10⁴. Temporally, both maximum drought area and peak intensity fluctuated but exhibited an overall declining trend from 1960 to 2002. After 2003, these indicators weakened markedly, suggesting a regional wetting tendency. Severe drought episodes were concentrated during three major periods: 1964-1968, 1977-1983, and 1993-2002. During extreme cases, the maximum affected area reached 6.9×10⁵ km², accounting for 88.4% of the total study area. Spatially, the analysis revealed pronounced heterogeneity. The north-central regions, particularly the Beijing-Tianjin-Hebei area, were identified as the epicenters of long-duration and high-severity drought events. In contrast, the southern portion of the plain was characterized by shorter and lower-intensity incidents. Centroid migration analysis identified two dominant pathways: due north and southwest, each accounting for nearly eighteen percent of the total events. Northward-moving droughts were typically large-scale events with migration distances exceeding nine hundred and sixty kilometers. Conversely, southwestward migration was dominated by localized droughts with displacement distances ranging from zero to seven hundred and twenty kilometers. Furthermore, heavy drought events exhibited clear spatial clustering, with their centroids gradually shifting from the northern reaches toward the central plain over time. In contrast, general drought events displayed multi-source dispersion characterized by a fan-shaped expansion from the southwest to the northeast. Overall, these results reveal distinct temporal trends and pronounced spatial heterogeneity in drought evolution across the Huang-Huai-Hai Plain. The three-dimensional dynamic identification framework effectively captured the continuity and migration of drought events and provided a more integrated representation than traditional static approaches. The identified post-2003 wetting tendency and directional migration characteristics reflected a significant shift in regional drought behavior. These findings supported the adoption of scPDSI for long-term monitoring in the Huang-Huai-Hai Plain and provided technical support for regional drought early warning and risk management.