Abstract: The magneto-elastic force sensor based on magneto-elastic effect is widely used in cable force measurement and monitoring of in-service bridge cables due to its simple structure, large output power, long service life, good dynamic response and strong overload protection. In order to solve the problems of poor consistency, difficult calibration, incomplete magnetization and coupling effect of the existing sleeve type and bypass type magneto-elastic sensors, a novel envelope type magnetic elastic sensor is proposed, which is based on flexibility. The detection coil of the printed circuit board has a better bonding effect. The steel cable stress measurement test is carried out. The results show that the cable linearity and sensitivity of the full-envelope magneto-elastic sensor are greatly improved and the magnetization effect is better. Further, the detection coil design of the flexible printed circuit board better realizes the reconfigurable design of the magnetic elastic sensor, which is convenient for installation and disassembly.