This paper investigates worsening flooding damage recently experienced in Phnom Penh, Cambodia. Contrary to Cambodia government leadership assertions that these floods have been caused by climate change, the study adopts an urban political ecology framework to uncover their actual underlying causes, which are rooted in political decisions, economic interests, and prevailing power dynamics. We argue that three processes have significantly contributed to the adverse flooding outcomes. First, rapid and uncoordinated urban land transformations have exacerbated flooding, disproportionately benefiting the economic elites. Second, inadequate governance of waste management systems and flood protection infrastructure has further compounded flooding. Last, state-sanctioned land reclamation projects of lakes and wetlands, which favor business and political elites, have displaced the urban poor and rendered the city, but particularly this group, more susceptible to flooding risks. All these processes are linked to Cambodia’s neopatrimonial political economic system, and are sustained by informal practices, coercion, and financial profits for elites. The urban poor tend to suffer the most, facing displacement risks and worsening vulnerability to floods. Our research transcends the rural-urban dichotomy, revealing the interconnectedness of this system across different contexts, including the influence of illicit gains from land enclosures on development. It also aims to contribute to international debates by highlighting that flood damage and losses are not solely caused by climate change but are also shaped by political-economic factors specific to each location.