The invention belongs to the technical field of computer security, and discloses a security event processing system and method based on computer network information. The system comprises a network monitoring module, a data acquisition module, a data mining module, a data processing module, a central control module, an information security evaluation module, an event analysis module, an event processing module, a data storage module, an alarm module and a display module. According to the system, most invalid and repeated information in the network security information can be filtered, the information processing efficiency and the information availability are improved, and the security event analysis and processing efficiency is effectively improved; meanwhile, real-time high-speed analysisand merging processing of the security events and presetting of merging logic of the merging events can be achieved, unified management of the security events is facilitated, and the security of computer network information is greatly improved; in addition, the security events are accurately analyzed and processed, and efficient execution of a network security function is ensured.