An optical power supply system includes power sourcing equipments, powered devices, a detector and a power supply controller. The power sourcing equipments each output feed light. The powered devices are provided so as to correspond to the power sourcing equipments, and each convert the feed light output from their corresponding power sourcing equipments into electric power. The detector detects an electric power amount required by a power supply target of the powered devices. The power supply controller controls, based on the required electric power amount detected by the detector, output of the feed light from each of the power sourcing equipments.