The invention relates to a COFDM communication based video monitoring system and method for electric equipment of a marine drilling platform. According to the technical scheme, the system comprises a camera unit, a COFDM communication transmitting unit, a COFDM communication receiving unit, a video monitoring system server and a power supply, wherein the camera unit is fixed on monitored equipment, the rear end of the camera unit is connected with the COFDM communication transmitting unit and the power supply, signal emitted from the COFDM communication transmitting unit is received through the COFDM communication receiving unit, and the COFDM communication receiving unit is connected with the video monitoring system server and the power supply. The invention has the beneficial effects that the inside condition of a switch cabinet can be visually monitored in all directions from multiple angles by videos so that the inside condition of the switch cabinet enclosed during the operating period is not a blind spot; when the switch cabinet has a fault, the content of videos about the inside condition of the switch cabinet before the fault can be used for analyzing the position and cause of the fault and providing a new technical method for fault diagnosis of the switch cabinet; when a mechanical fault, an insulation fault, switch fault or current-carrying fault happens, the fault can be discovered and handled timely.