Abstract: With the continuous expansion of deepwater oil and gas development into high-temperature and high-pressure formations, issues such as the inadequate adaptability of existing drilling well control strategies in complex environments and the unclear timing of emergency response become increasingly prominent. Therefore, there is an urgent need to construct a systematic safety analysis method to support the optimization of well control strategies. To systematically identify the key factors of blowout risk in high-temperature and high-pressure drilling and reveal their dynamic evolution mechanisms, based on the systems-theoretic accident model and processes, the STAMP/STPA method was applied to identify unsafe control behaviors and their causes in the well control system, construct a safety control structure adapted to high-temperature and high-pressure environments, and further comparatively reveal its differentiated risk characteristics relative to conventional drilling. On this basis, the system dynamics method was introduced to establish a simulation model for the evolution of well control safety level. The model was used to simulate the dynamic evolution process of system safety state under coupling scenarios of different risk causes, and elucidate the influence patterns of multi-factor interactions on well control safety level. Simulation results indicate that systematic analysis and dynamic modeling can effectively identify key risk pathways and control weak links in high-temperature and high-pressure drilling, and construct a critical curve of well control safety level. On this basis, the well control safety state was divided into different grades, active and passive combined well control strategies for typical causative scenarios was proposed, and differentiated control measures at the initial stage of risk and the critical state were clarified. The research conclusions can provide theoretical support and a decision-making basis for the active prevention and precise control of blowout accidents in deepwater high-temperature and high-pressure drilling.