PURPOSE: To always enables accurate measurement of magnetic value regardless of the direction of a magnetic field using an electroconductive material for the sensing of magnetism.

CONSTITUTION: An electroconductive material 1 is given a direction of motion with an exciting unit to perform an excitation. Sensor sections 1, 2 and 3 of a magnetic sensor are so arranged to be assembled to be vertical to each other and voltage signals obtained with the sensor sections 1-3 are subjected to a removal of high frequency portions with a filter circuit via an amplification circuit as required to obtain components in directions of intensity of a magnetic field of an object to be measured. For example, the intensities of the magnetic field separately in directions X, Y and Z are determined with the sensor sections 1-3. At a certain time, the voltage obtained with the sensor sections 1-3 is considered as components in directions (X, Y and Z) of intensity the magnetic field as the object to be measured and thus, the values of the intensities of the magnetic field as the object to be measured can be obtained by determining a sum of vectors.