Abstract: The cable-stayed bridge cables are used to provide structural support for the bridge panel. As a critical force component of the bridge, the condition of these cables is intricately linked to the overall safety and integrity of the structure. Due to prolonged service, they are susceptible to internal corrosion and wire breakage caused by rainwater infiltration into aging and damaged sheath surfaces during operation, thereby posing a significant safety risk for the bridge. The magnetic flux leakage (MFL) method serves as an effective approach for detecting internal damage in cable-stayed bridges. This study employed a developed MFL system specifically designed for cable-stayed bridges to conduct defect detection tests. Firstly, the DC excitation method was employed to detect grooves on the cable body surface, and the impact of sheath breakage on the MFL signal was examined. Subsequently, surface and internal defects were inspected using the combined DC and pulse excitation techniques to detect defects and localize cable-stayed bridges. This research could offer valuable insights for engineering applications related to cable defect detection.