The invention is applicable to the technical field of 1000MW nuclear power and provides a safety control system and device for nuclear power plants. The system comprises that a field controller acquires and integrates alarm signals generated by alarm signal generation equipment; an intelligent controller determines and transmits integrated alarm signal position information to a server, so that the server transmits the received alarm signal position information to a closed-circuit television controller; the closed-circuit television controller triggers configuration instructions of a closed-circuit television and transmits the configuration instructions to a video control work station, so that the video control work station can call the corresponding camera shot video to corresponding monitors to be displayed. By means of the system and the device, the consumption of manpower and material resources can be reduced.