Live operation of 10 kV lines is carried out in distribution network, in which J-type wire clamp are widely applied to live-line connection/disconnetion operation. It is of great significance to study the working status of J-type wire clamp. Using the 3-D multi-physics coupling method, an equal proportion model and a 3-D mechanical-electrical-thermal coupled model are established to analyze the stress distribution, current density distribution and temperature distribution of 10 kV J-type wire clamp. The result shows that the stress distribution, current transmission and temperature distribution are extremely uneven. The maximum stress of contact surface reaches 6.8×10⁹ N/m², and the maximum displacement of the wire clamp is 1.04 mm. The current between the wire clamp and the wire is concentrated in the 1/4 area of the contact surface, where more than 60% of the current flows, resulting in the utilization ratio of the contact surface is low, but the current density distribution between the wire clamp is relatively uniform. The highest temperature occurs in the groove of the wire, with a value of 50 K.