To detect wire breakage or the like of a sensor before detecting genuineness or the like of a card, and to execute a proper process.

This IC card reader is provided with: the sensor 10 configured as a magnetic differential type having a detecting coil 12 and a pair of exciting coils 13c, 13d wound around a magnetic core in a position on an inlet side of a card feeding path 4; a feed drive means leading the IC card 3 to a reading/writing position when the sensor 10 detects a contact terminal part 3b of the IC card 3; and a wire breakage diagnostic means diagnosing the wire breakage or the like of the sensor 10 by a voltage value of an output signal outputted from the detecting coil 12 by exciting the exciting coils 13c, 13d when the sensor 10 does not detect the contact terminal part 3b of the IC card 3. Thus, the wire breakage or the like of the sensor 10 is detected in advance.