System for identifying paired ID cards

A system for identifying ID (identity) and an ID card using the same are provided in the present invention. The ID card includes a card case, a first conducting electrode and a plurality of second conducting electrodes. The first conducting electrode and the second conducting electrodes are disposed in the card case. At least a specific second conducting electrode is electrically connected to the first conducting electrode to represent a specific ID. A card reader for reading the ID card includes a transmitting unit, a plurality of receiving units and a control circuit. The transmitting unit is disposed at the position corresponding to the first conducting electrode, and the receiving units are disposed at the position corresponding to the second conducting electrodes when the ID card is disposed on the card reader. The control circuit is coupled to the transmitting unit and the receiving units. When the ID card is close to the card reader, the transmitting unit transmits a wireless signal. The control circuit determines the ID of the ID card according to the receiving unit(s) which receive(s) the wireless signal.