Abstract: Taking butyl rubber as matrix, Fe73.5Cu1Nb3Si13.5B9 nano particles as magnetic reinforced material, the composite film was prepared by using compression molding method and its piezomagnetic property was studied. The results show that the composite film had superior piezomagnetic property when the AC frequency was low, however, its repeatability and temperature stability had large error. The resistance, reactance, impedance, rangeability of resistance, rangeability of reactance and rangeability of impedance decreased with the increase of the AC frequency when the compressive stress was constant. When the AC frequency was constant, the reactance and impedance decreased with the increasing of the compressive stress, while the resistance, rangeability of resistance, rangeability of reactance and rangeability of impedance increased with the increase of the compressive stress.