An antenna and a wireless communication device which are suitable for an RFID system and in which radiation characteristics are prevented from being changed as a result of impedance adjustment are configured such that the antenna includes a first loop electrode that has an external shape of a regular polygon or circle and that includes a pair of open ends, feeding portions arranged inside the first loop electrode, a second loop electrode connected to the feeding portions, and a coupling electrode that couples the first loop electrode and the second loop electrode to each other. The wireless communication device is obtained by coupling the wireless communication element which processes a high-frequency signal to the feeding portions.