Under the interactive influence of climate change and intensive human activities, the evolutionary mechanism of hydrological drought in the Jitai Basin exhibits significant stage-specific differences. Based on data from 1959 to 2023, the Pettitt test on the R/P sequence was employed to delineate the reference Period, transition period, and change period. By integrating the improved monthly water balance model with scenario simulations, this study analyzes the differentiated impacts of climate change and human activities on drought characteristics across different stages. The results show that the runoff coefficient in Shushui, Wujiang, and Tongjiang basins shifted around 1980 and 2008. After a significant increase in runoff effect (R/P) during the transition period, it declined in the change period. Compared to the reference Period, the drought intensity and duration in the three typical basins decreased significantly during the transition period but rebounded in the change period, with average drought intensities increasing by 46.2%, 26.9%, and 25.9% respectively compared to the transition period. High temperatures and low precipitation in summer and autumn are key drivers of hydrological drought in the Jitai Basin, demonstrating strong sensitivity to drought intensity: a 10% decrease in precipitation during this period increases drought intensity by 0.14 to 0.23, exhibiting a diminishing marginal effect. However, compared to the reference Period, human activities dominated the change period, causing variations in runoff depth and drought intensity that exceeded those from climatic factors. The multi-stage driving factor quantification method developed in this study reveals the nonlinear regulatory effects of different factors on hydrological drought intensity, providing a reference for drought early warning and long-term trend prediction in the Jitai Basin.