The invention relates to an on-line intelligent system for safety emergency based on multiple communication networks and sensing equipment, and belongs to the technical field of remote intelligent safety supervision equipment. The system consists of an on-line supervision module, a safety production cloud data center, and an emergency rescue module. The system is characterized in that the input end of the safety production cloud data center is in parallel connection with the on-line supervision module and an early-warning analysis auxiliary decision module; the output end of the safety production cloud data center is in parallel connection with a monitoring early-warning module, a video re-check intelligent control module, the emergency rescue module, and an information push module; and a data transmission and sharing switching module connected with the monitoring early-warning module is connected with a business subsystem. The system integrates on-line dynamic monitoring of safety production, alarm and management, hidden danger removal and intelligent law enforcement into one body, is well targeted, is high in applicability, and is high in efficiency of safety control and management. The system solves a problem that a conventional mode of segmented and manual monitoring is difficult in information integration and rectification, cannot achieve the real-time monitoring and quick processing of accidents, and is low in management efficiency.