Automatic magnetic measurement for bar specimens of soft magnetic materials was studied by means of the yoke method. A new magnetizing apparatus was designed to reduce to zero the difference between the magnetic flux densities induced in the center and the end search coil, in order to correct the self-demagnetization. This method allows accurate, magnetic measurements to be made for bar specimens of magnetic pure iron, as well as for the conventional ring specimens. On the other hand, a quicker measurement speed of the hysteresis loop and a larger sectional area shows an increase in the apparent coercive force due to the phenomenon of the delay of magnetization in this measurement method.