PROBLEM TO BE SOLVED : To provide a device to be used for remotely monitoring a real estate or a person to be monitored or protected. SOLUTION : This remote monitoring system is provided with video photographing devices C arranged on a real estate 1 to be monitored and capable of presenting monitored data, a central station 2, and a data link ISDN arranged between the devices C and the station 2 to transmit monitored data. The station 2 is provided with a video telephone system BT for receiving monitored data from each device C through the data link and a mobile telephone system MT for exchanging information with a person to be protected based upon monitored data.