Rapid urbanization and human activities have a profound impact on the hydrological process in Taihu Basin. This paper constructed three indices include the water level rising (ΔZ), the rate of water level rising (k₁) and the rate of water level recession (k₂). Based on the observation data of daily rainfall and water level during 1961-2014, we try to reveal the variation characteristics of the water level and possible driving factors in the rainfall process in the Hangzhou-Jiaxing-Huzhou region. The results indicate that:(1) The rainfall shows an increasing trend, but the ΔZ shows a decreasing trend during the rainfall process. Especially, the average water level rising shows a significant decreasing trend and the abrupt change occurs in the year 2000 AD. The decreased ΔZ mainly occurs in the rainfall intensity ranged from 10 mm/d to 50 mm/d after 2000 AD. The ΔZ shows an increased trend in heavy rainfall process above 50 mm/d. (2) The rainfall in the east shows a significantly increasing trend than in the west. However, ΔZ in many stations is declining, which is more significant in the south. These changes is inseparable from the flood discharge project in the Hangzhou-Jiaxing-Huzhou region. (3) Through the analysis of the k₁ and k₂ in the rainfall process, k₂ is increased, which indicates that the development of water conservancy facilities and orderly scheduling has improved the flood discharge capacity in recent years. This change may be the main cause for the declined k₂ in a certain intensity of rainfall after 2000 AD. The ΔZ remained high in the heavy rainfall process, which can be related to that the current flood discharge capacity that cannot resist the increase of ΔZ. In addition, the incipient rising water level has increased significantly in recent years, which also makes a certain impact on the flood in the study area.