A wireless IC device that is miniaturized, allows simple and low-cost mounting of a wireless IC, and eliminates the possibility of damage occurring to the wireless IC due to static electricity, and an electronic apparatus equipped with the wireless IC device, includes a wireless IC chip that processes transmission and reception signals, and a feeder circuit substrate that includes a resonant circuit having an inductance element. Feeder electrodes are provided on a surface of the feeder circuit substrate and are electromagnetically coupled to the resonant circuit. The feeder electrodes and are electromagnetically coupled to radiation plates and provided for a printed wiring board. The wireless IC chip is activated by a signal received by the radiation plates and a response signal from the wireless IC chip is radiated outward from the radiation plates.