Abstract: A device for measuring a magnetic property of a magnetic reproducing head at a measurement point thereon, the device which applies a first magnetic field which oscillates at a predetermined oscillation frequency to the measurement point, applies a second magnetic field of which strength changes slower compared with the oscillation frequency of the first magnetic field to the measurement point, detects a signal generated by the magnetic reproducing head according to the total strength of the first magnetic field and the second magnetic field, extracts amplitude components synchronizing with the oscillation frequency from the signal, and calculates changes of the signal against the total magnetic field strength based on the extracted amplitude components.