The stress impedance effect is studied for the Co66Fe4Cr2Si12B16 amorphous ribbons under bending strain. One of the amorphous ribbons is in as-cast state and the other is treated by pulse current, and the both amorphous ribbons are of the negative magnetostriction. The experimental result shows that the amplitude ratio of the output voltage from the two ends is larger than 40% for the pulse current annealed amorphous ribbon of 50 mm in length only under a bending strain of 5 mm deflection. The stress impedance sensitivity can be improved by the pulse current annealing at 35 A/mm2 and 2 Hz for 30 s. The bending impedance increases with the applied compressive stress, and decreases with the tensile stress, and can be used to develop a new force sensor with large gauge factor and some novel smart materials.