A magnetic sensor, consisting of a thick Bi-Pb-Sr-Ca-Cu-O (BPSCCO) film, is fabricated in such a manner that it retains a residual resistance at the boiling point of liquid nitrogen (77.4 K). The sensitivity of this sensor to an excitation magnetic field between 0 × 10-4 and 10 × 10-4 T, is about 7%/(10-4 T), being about seven times greater than that of a giant magnetoresistance sensor. Experimental results reveal characteristics that include the dependence of the resistance of the sensor on the temperature, magnetic field, and current density. In addition, the method for the fabrication of the BPSCCO magnetic sensor is discussed. © 2002 Elsevier Science B.V. All rights reserved.