Abstract: [Objective]Slope instability triggered by water storage fluctuations is a common disaster in the context of large-scale hydropower development in mountainous and canyon regions. Since the beginning of the new century, with the intensification of hydropower development, there has been an increased demand for identifying the potential hazards of this specific type of disaster. InSAR observation has largely addressed the challenge of large-scale multi-target deformation identification; however, due to the instantaneous nature of the observations, it cannot detect latent hazards that have not yet manifested as deformations. Therefore, there is an urgent demand to summarize the geomorphological signatures that trigger slope instability due to water storage fluctuations, to aid in the identification of such hazards. Since the large-scale impoundment of the Baihetan Reservoir in 2021, a series of slope instabilities triggered by water storage have provided a unique opportunity to define the geomorphological signatures of water-induced disasters. [Methods]By integrating InSAR observations, a series of geomorphological parameters, and optical imagery. Specifically, utilizing 228 ascending and 234 descending Sentinel-1A images from 2020 to 2023, employing the DS-InSAR technique to identify deformed slopes triggered by water storage fluctuations. [Results]The results show that the explanatory power of geomorphological parameters such as toe height, slope, aspect, and roughness in relation to disaster triggers. Furthermore, the findings show a correlation analysis incorporating rock layer structures, lithological variations, precipitation, and water storage level changes. [Conclusion] The strength of lithology, slope structure, and geomorphological parameters in the Baihetan Reservoir area, along with their corresponding numerical ranges, form composite geomorphological signatures that can be used for early identification of hazards associated with water-induced slope instability. Additionally, we discovered that, beyond the effects of water storage, precipitation events also play a significant role in triggering slope instability in the reservoir area, highlighting the importance of this factor as a driving force. [Significance] This insight is of substantial value for disaster prevention and reduction efforts in the context of hydropower development, contributing to the optimization of site selection and operations for hydropower stations. Furthermore, it provides a reference for the susceptibility assessment of other types of unstable slopes.