The piezomagnetic properties of rapidly quenched Fe73.5Cu1Nb3Si13.5B9 alloy strips were investigated in as-quenched state and after annealing for 2 h in vacuum in the temperature range of 100–300 °C. The impedance of amorphous strips increases with frequency, and sensitively decreases with stress increasing, especially in the frequency range of 10–100 MHz. The impedance increases approximately linearly with frequency below the critical frequency, but begins to decrease non-linearly with frequency above the critical frequency. The higher the point compressive stress is, the smaller the critical frequency will be. The stability of piezomagnetic properties is very excellent. The impedance of amorphous strips after annealing, especially at 300 °C, decreases very strongly. The impedance and the absolute values of the sensitive degree of couple layers’ amorphous strips are lower than those of single layer strips.