The utility model provides a power supply cable jointing clamp with locking structure, last tong arm connect through the activity hinge with lower tong arm, the right -hand member fixed mounting of last tong arm go up the binding clip, go up the first pincers handle of left end fixed mounting of tong arm, the right -hand member fixed mounting of lower tong arm under the binding clip, the left end fixed mounting second pincers handle of lower tong arm, second pincers handle on through screw thread installation locking bolt, fixed mounting soft iron on the locking bolt, first pincers handle on fixed mounting electromagnetic core, the last solenoid that twines of electromagnetic core, compression spring's top fix on last tong arm, compression spring's bottom mounting is under on the tong arm. The utility model discloses a fixed mounting electromagnetic core on the first pincers handle, the design of going up the tong arm and installing compression spring down between the tong arm utilizes the locking of electromagnetic force realization jointing clamp, and compression spring can make the jointing clamp more laborsaving simultaneously, and scientific and reasonable, simple structure are designed to it.