A magnetoresistive magnetic imaging sensor for identifying a magnetic image comprises a PCB and several magnetoresistive sensor chips, wherein the several magnetoresistive sensor chips are located on the PCB, and the PCB is perpendicular or parallel to the magnetic image detection surface. It has a lateral detection mode and front detection mode. In the lateral detection mode, each side face of the several magnetoresistive sensor chips is parallel or coplanar with the side of the PCB, and parallel to the magnetic image detection surface. The several magnetoresistive sensor chips have the same magnetic sensing direction. In the lateral detection mode, the adjacent magnetoresistive sensor chips are stacked, while in the front detection mode, the adjacent magnetoresistive sensor chips are arranged in a staggered manner, in order to achieve continuity of the detection area in the magnetic image detection surface. The magnetoresistive magnetic imaging sensor may also comprise a permanent magnet assembly and a housing. The sensor has several advantages, including continuity across the detection area, good signal reproduction, high sensitivity, and low power consumption.