Climate change and the operation of hydraulic projects have significantly altered the water cycle in the Three Gorges Reservoir area. The Three Gorges Reservoir area has experienced recurrent seasonal droughts in recent years. Analyzing the evolution characteristics and driving mechanisms of seasonal agricultural drought in this? region, as well as coupled with the quantitative determination of yield reduction thresholds under current drought defense conditions, is significantly important for developing a systematic response to agricultural droughts. Firstly, the spatiotemporal evolution of seasonal agricultural drought in the reservoir area from 1982 to 2022 was investigated, based on the Standardized Soil Moisture Index (SSMI). Furthermore, additional analyses were conducted using Path Analysis to explore key driving factors. Additionally, drought return periods and representative drought years were determined using Copula theory, and historical typical drought scenarios are extracted. On this basis, effective rainfall was introduced to improve the parameters of the Jensen model, considering losses due to evaporation, interception, and runoff. A new method for calculating the drought-induced crop yield reduction thresholds under historical typical drought scenarios and current defense conditions was proposed based on the improved Jensen model. recurrence of historically typical drought. The results showed that agricultural droughts in the Three Gorges Reservoir area intensified between 1982 and 2022, with significant spatiotemporal variability. Specifically, the tail section of the reservoir was identified as the high-frequency agricultural drought-prone area, while the middle reaches were characterized by long-duration, high-intensity, and severe droughts. Similarly, the upper reaches were prone to extreme, long-duration droughts. Further analysis revealed that future agricultural droughts in the reservoir area were expected to decrease overall. The key driving factor for summer-fall droughts was precipitation, while potential evapotranspiration was the directly influenced factor for winter-spring consecutive droughts. Finally, under the current water conservancy defense conditions, drought-induced crop yield reduction thresholds for return periods of 2, 5, 10, 20, and 50 years were calculated as 1.23%, 5.12%, 8.13%, 15.44%, and 22.32%, respectively. Overall, these findings provided technical support for drought-resilient water resource planning, drought replenishment scheduling, and scenario-based water management in the Three Gorges Reservoir area.