And an antenna coil (202) comprising a magnetic core (4) and a flexible substrate (5) mounted on the circuit board (9) constituting the antenna device. First coil portion having a plane parallel to the principal coil axis of the magnetic core (4) (2a) is constructed out with the third coil and the first coil (21) (23), the second coil portion (2b) is constructed out with the fourth coil and the second coil (22) (24), first and second coil portions (2a, 2b) provided the conductor-free portion (8) between. Provided with the projecting portion (6) on the flexible substrate (5), pulling out the first to fourth coil connection portion to the protruding portion (6). Perform connection between the coils on the circuit board by connecting to conductor patterns on the circuit board with the protrusion of the flexible substrate (5) (6) (9), constituting the antenna device.