针对南海某水下生产系统低压回路化学注入压力异常下降问题，首次提出并实施了一套完整的应急充压解决方案。通过系统性的方案选型、液压插盘改造和专用充压装置设计，结合陆地模拟试验验证，成功完成了海上应急充压作业。实践表明，该应急充压方案有效维持了系统压力稳定，避免了井口自动关停风险，保障了水下生产系统的安全连续运行。研究不仅解决了实际工程问题，同时为类似水下生产系统的压力异常处理提供了可借鉴的技术方法和实践经验，对保障水下生产系统的可靠性和安全性具有重要意义。

This paper addresses the abnormal pressure drop in the low-pressure loop chemical injection of a subsea production system in the South China Sea by proposing and implementing a comprehensive emergency pressure recharging solution for the first time. Through systematic solution selection， stabplate modification， and the design of a dedicated pressure recharging device， combined with validated onshore simulation test， the offshore emergency pressure recharging operation was successfully completed. Practice demonstrates that this emergency pressure recharging solution effectively maintains system pressure stability， avoids the risk of automatic wellhead shutdown， and ensures the safe and continuous operation of the subsea production system. This study not only resolves a practical engineering issue but also provides valuable technical methods and practical experience for handling similar pressure abnormal in subsea production systems， and is of great significance for ensuring the reliability and safety of subsea production systems.