The invention discloses a security monitoring method and system based on power cloud, and the system achieves the real-time alarm of security events such as abnormal operation of a host machine, illegal processes, network abnormity and the like through the monitoring of information such as the operation state of the host machine, a key process, a network state and the like. Through monitoring information such as a virtual machine operation system and session connection, real-time alarm of security events such as abnormity and illegal access of the virtual machine operation system is realized.Real-time alarming of management host abnormity, cloud platform state abnormity and virtual machine full life cycle safety events is achieved by monitoring the operation state of the cloud platform, the operation of the virtual machine and other information.On the basis, a network security comprehensive management and control mechanism for checking, monitoring, analyzing and alarming is established to form a complete set of electric power regulation and control cloud security monitoring system, so that the safe operation of the regulation and control cloud is ensured.