PROBLEM TO BE SOLVED: To provide a telephone system housing an interphone which allows for monitoring operation with a plurality of terminals, when performing automatic patrol monitoring of the situation of rooms of cared persons in a care facility, and also allows for continuation of monitoring of the same room depending on the situation, or re-monitoring of a room that was monitored just before.SOLUTION: A plurality of extension terminals 3A-3M capable of monitoring operation are housed, and by a command inputted from the key operation part 36 of the extension terminal, voices inputted to the microphones 24A-24N of monitor extension terminals 2A-2N are reproduced sequentially from the handset 34 or speaker 35 of the extension terminal 3 at predetermined intervals, and by a command inputted from the key operation part 36 while monitoring, continuation of monitoring of one monitor extension terminal or switching to a monitor extension terminal that has been monitored just before is allowed. Furthermore, video display of network cameras 6A-6N interlocked with the monitor extension terminals 2A-2N is allowed in a video display extension terminal 4.
