The study analyzed temperature, precipitation, and runoff trends in Baiyangdian Lake Basin from 1957 to 2012. Results showed a significant warming trend since 1988, with temperatures rising more in winter and summer. Annual precipitation decreased, especially in summer. This, along with increasing temperatures, worsened dry and hot conditions, leading to decreased runoff and more frequent lake-drying. Runoff decreased due to the combined effects of temperature and precipitation, with a negative correlation between runoff and temperature, and a positive correlation with precipitation. Summer runoff at specific hydrological stations decreased, indicating a clear response of runoff to precipitation changes. The study aims to provide data for improving the ecological environment and water resource management in the area.