The present invention is disclosed to provide an NFC antenna using dual resonance, wherein a closed circuit is formed by a capacitor and a loop antenna, and a relay unit is attached to a portable wireless terminal that forms a resonance to a predetermined frequency signal mutually transmitted between a portable wireless terminal reader and an NFC chip, and in the course of communicating between the NFC chip and the reader, the relay unit relays a signal transmitted by the reader to an NFC antenna unit, and the NFC chip relays a signal transmitted through the NFC antenna unit to the reader to thereby increase a recognition distance capable of obtaining predetermined information.