Abstract: The open-loop permanent magnetic flux leakage detection sensor of steel wire rope is widely used in steel wire rope defect detection in advantage of its excellent detection performance. Based on the principle of open-loop permanent magnet magnetization magnetic flux leakage detection sensor and the structural analysis of open-loop magnetizer, the finite element model of open-loop permanent magnet magnetizer and its probe shoe was established by using ANSYS finite element simulation analysis method, and the defect characteristic curve of steel wire rope under different width and depth of probe shoe was extracted and analyzed. Different detection results corresponding to different probe shoe groove sizes were revealed. The results illustrate that the size of the groove has a certain influence on the detection results, and it is considered that there is an optimal size under which the detection results of the shoe reach an optimal value.