The invention provides a device and method for controlling electric potential transfer current and electric arcs of extra high-voltage live working. The device comprises an electric potential transferunit and a control loop. The electric potential transfer unit comprises an electric potential transfer loop and used for transferring electric potential in the extra high-voltage live working. The electric potential transfer loop comprises a clamping mechanism, a connection device, an insulation wire and a connection terminal, wherein the clamping mechanism, the connection device, the insulationwire and the connection terminal are successively connected. The control loop is used for limiting the amplitude value of the electric potential transfer current and the length of arcs produced in in-and-out equipotential processes. The control loop comprises a gap and a metal oxide lightning arrester serially connected with the gap. The control loop is serially connected to the electric potentialtransfer loop. According to the invention, the device is simple in structure and convenient to use; the control loop comprising the gap and the MOA in the electric potential transfer loop is introduced to control the electric potential transfer current and electric arcs are controlled, so the electric potential transfer current and electric arcs are obviously inhibited.