The present invention provides an RFID tag excellent in the diffusion of heat. The RFID tag includes a base, an antenna pattern that is provided on the base and forms a communication antenna, a circuit chip that is electrically connected to the antenna pattern and performs radio communication via the antenna, a cover that is provided in close contact with the base in such a manner as to cover the antenna pattern except a prescribed region including the circuit chip, and an insulating thermal diffusion material that covers the prescribed region and is in thermal contact with the circuit chip. The insulating thermal diffusion material has thermal conductivity higher than the thermal conductivity of the cover.