A power supply system capable of supplying power from a power transmitter to a power receiver in an electrically non-contact manner, in which a power transmission module is attached to the power transmitter and a power reception module is attached to the power receiver. The power transmission module has a plurality of transmission-side coils for transmitting power and a plurality of transmission-side switches for turning on/off operation of the transmission-side coils. The power reception module has a plurality of reception-side coils for receiving power, a plurality of reception-side switches for turning on/off operation of the reception-side coils and, further, has a determination circuit for performing control so as to operate any of the transmission-side coils and any of the reception-side coils in a combination realizing highest power transmission efficiency.