In order to promote the precise governance goals of accident risks，a research method combining process-tracking based on actor network theory and case comparative analysis was adopted to study the weak prevention generation mechanism in the process of accident risk governance. Firstly，the technical environment for analyzing the evolution process of accident risk was clarified，including prepositive contexts，structural scenarios，and developmental circumstances，as well as the analysis logic based on Lens Model and dimensions of time，space，and structure，to provide a research foundation for the integrity analysis of accident risk production process. Secondly，based on the case comparative analysis of the tracking of the interaction process between different types of actors and risks，the role change picture of the core actors，homeowners and rainstorm，in the process of accident/disaster risk governance and accident/disaster generation was presented integrally. Finally，a comparative analysis and reflection of case studies based on tracking the interaction between different types of actors and risks were summarized，and the essence and generation mechanism of weak prevention in the process of accident risk governance were proposed. The results indicate that the mixed interaction between human and non-human actors can continuously activate the emergence and mutual construction process of new actors，new intersectionality，and new vulnerabilities in the system，subsequently resulting in the non-stationary evolution of accident risk production environment and risk structure，which leads to intervention failure and recurrence of weak prevention in the process of accident risk governance.