In recent years, extreme meteorological and hydrological events tend to be more and stronger, the frequent occurrence of flood disasters in a rapidly evolving environment has brought severe challenges to both social and economic development. This study concentrates on the Chongqing, one of two principal cores within the megacities of western China, part of the Chengdu-Chongqing urban agglomeration. This city's terrain, predominantly hilly and mountainous, together with its proximity to upstream rivers and the backwater of the Three Gorges Reservoir area (TGRA), highlights its exposure to the threat of flood disasters. This study focuses on Chongqing's historical flood disaster events to assess the current state of flood prevention and disaster reduction efforts within the city. We further analyze the impact of various factors – including hydrology, geography, topography, urbanization, and meteorological conditions – on both the frequency and intensity of flood disasters in Chongqing. Alongside these causal factors of flood disasters, we further delve into the analysis of Chongqing's disasters – forming environment and the entities that bear these disasters. Finally, countermeasure suggestions for flood management in the central city of Chongqing are presented. The findings indicate that the occurrence of flood disasters in Chongqing is influenced by a myriad of factors, and the special location and the characteristics of the mountain city determine the difficulty of flood prevention and management in Chongqing. Notably, the city's complex terrain and numerous rivers meet the conditions conducive to flood disasters. Given the evolving circumstances brought about by meteorological hydrology and socio-economic developments, it is imperative to proactively reassess and optimize Chongqing's urban flood disaster prevention system. This should be done in accordance with the unique flood disaster characteristics that have emerged following the completion of the TGRA and the current flood control and waterlogging prevention capacity of the urban area.