To provide a photoelectric composite wiring component combining both characteristics of low power consumption of transmission by electric wiring and large transmission capacity of optical transmission by optical wiring, and exhibiting a high power efficiency for the transmission capacity. [MEANS FOR SOLVING PROBLEMS] A mechanism for switching between transmission of a transmission signal over an electrical transmission path and that over an optical transmission path depending on the modulation rate or the transmission rate of the transmission signal is provided. When the modulation rate or the transmission rate of the transmission signal is low, power supply to an optical transmitting/receiving section is stopped and the signal is transmitted over the electrical transmission path, thus achieving low power consumption. When the modulation rate or the transmission rate of the transmission signal is high, the signal is transmitted over the optical transmission path, thus achieving a large transmission capacity.