An RFID tag including a first part which has a first base and a communication antenna formed on the first base by use of a paste of resin material mixed with metallic filler; and a second part disposed on the first part, which has a second base, a metallic patch disposed on the second base and electrically connected to the antenna on the first part, and a circuit chip connected onto the metallic patch via a bump, the circuit chip performing radio communication via the antenna.