To provide a low-cost optical CATV service for individual subscribers by utilizing a conventional video broadcast service network.

A head end device 10 uses a broad band FM modulator 100 to convert a subcarrier multiplex signal 200, that provides a conventional video broadcast service, into a broad band FM signal 210 and uses this signal to apply intensity modulation to an optical signal 230. On the other hand, FM modulators 310a, 310b convert subcarrier multiplex signals 300a, 300b, that provide a service for individual subscribers, into FM signals 320a, 320b and use the FM signals to apply intensity modulation to optical signals 340a, 340b. The optical signal 230 and the optical signals 340a, 340b are respectively multiplexed and the resulting signals are sent to optical CATV terminals 20a, 20b. An optical receiver 410a in the optical CATV terminal 20a converts the received optical signal 230, 240a into a high frequency signal 420 and a broad band FM demodulator 430a demodulates the high frequency signal 420a.