Abstract: A test circuit was designed and built, which is based on one-stage and two-stage magnetic pulse compression systems without external demagnetization circuits, so as to test the dynamic magnetic characteristic of Ni-Zn ferrite magnetic core under excitation pulses of microsecond and sub-microsecond level. The hysteresis loop of the magnetic core was calculated by tested voltage and current from the magnetic switch, with which various characteristic parameters of the magnetic core under the two kinds of excitation pulses can be easily gained, including saturated magnetic induction intensity, residual magnetic flux density, square ratio, magnetic flux density variation, coercive force, saturated magnetic-field intensity and magnetic hysteresis loss of unit material volume. The comparison of t