The invention discloses an Internet based intelligent hazardous chemical substance control system and method, and belongs to the technical field of hazardous chemical substance control. The system comprises a video monitoring module, a hazardous chemical substance information detection module, a data collection module, a central control module, a wireless communication module, a data storage module, a real-time positioning module, a wireless base station, a remote server, an intelligent mobile end, an alarm module and an expert module. The hazardous chemical substance information detection module can detect parameters including occurrence of leakage, internal pressure of a container, liquid level, concentration, temperature, humidity, flow, inertia and opening state of a casing of hazardous chemical substances. Detection data is comprehensive and complete, the real-time state of the hazardous chemical substances is controlled comprehensively, the control safety is improved, expert knowledge is used via the expert module, scientific and accurate control strategies can be made, and control of the hazardous chemical substance is more professional.