Abstract: The ecological water level serves as a crucial indicator for assessing the health of lakes. Xidongting Lake is a significant component of the Dongting Lake ecosystem. To scientifically identify the evolutionary characteristics and influencing factors of the ecological water level in Xidongting Lake, this study collected daily water level data from four hydrological stations: Shiguishan, Niubitan, Xiaohekou, and Nanchu, spanning over the past 60 years. The IHA-RVA method and intra-annual distribution method were employed to calculate both the ecological water level and its guarantee rate; additionally, an analysis was conducted on the occurrence time and duration of high and low water levels. The research findings indicate that due to the construction of cascade hydropower stations along the Li River and Yuan River, abrupt changes in water levels at Shiguishan Station occurred in 1985, while those at Niubitan Station were noted in 1992. Furthermore, abrupt changes in water levels at Xiaohekou Station and Nanchu Station were observed in 2003. The annual guarantee rates for both the suitable ecological water level and the minimum ecological water level at the four hydrological stations exhibit a downward trend, with the most pronounced changes observed at the Shiguishan Station located in the lower reaches of the Li River. Specifically, the guarantee rate for the suitable ecological water level has decreased from 47.21% to 28.32%, while that for the minimum ecological water level has declined from 78.50% to 48.78%. At both Shiguishan Station and Niubitan Station in the lower reaches of the Yuan River, there has been a postponement in high water levels along with a reduction in their duration; conversely, low water levels have occurred earlier and persisted longer. Similarly, at Nanju Station and Xiaheju Station, low water levels have also advanced in occurrence time and increased in duration, whereas high water levels have been delayed and shortened in duration. This study examines water levels in West Dongting Lake, as well as identifying changing characteristics associated with these metrics. The findings aim to provide valuable insights for assessing ecosystem health within West Dongting Lake's lake and wetland environments as well as contributing to research on biodiversity within these ecosystems.