Disclosed is a radio device comprising a notch antenna, wherein the notch antenna is comprised of a circuit substrate including a ground portion and a notch portion opened at one end thereof, and a radio circuit portion provided on the circuit substrate for supplying a high-frequency current to the notch portion. In the radio device, a bent-back portion formed so as to be connected to the ground portion and to extend the notch portion is provided on one end side of the circuit substrate. This ensures that the length of the notch antenna is reduced, the size of the antenna can be reduced, antenna efficiency is enhanced, and deterioration of gain due to the influence of a human body can be suppressed.