In an RFID system including an RFID tag and an RFID reader for performing wireless communications with the RFID tag, an RFID relay antenna has a first loop antenna for electromagnetic induction coupling with an antenna at the RFID tag, a second loop antenna that is provided apart from the first loop antenna and for electromagnetic induction coupling with an antenna at the RFID reader, and wires for connecting the first loop antenna and the second loop antenna so as to form one closed loop and for conveying an induced current generated at the first and second loop antennas to the second and first loop antennas, respectively.