The invention provides a living voltage transformer replacement device for a metering cabinet. The living voltage transformer replacement device comprises a vehicle, a contact arm, a static contact and a secondary socket, wherein the vehicle is provided with a voltage transformer and a fuse; the secondary socket is disposed on the front panel of the vehicle; one side of the secondary socket is electrically connected to the secondary-side measuring line of the voltage transformer and a vehicle position signal line; the other side of the secondary socket is electrically connected to an instrument room; a cylindrical cavity is disposed in the contact arm and is provided therein with a spring, a damping resistor, a first support ring, a second support ring and a metal contact rod; and one endthe spring is connected with the bottom of the contact arm. A special contact arm structure and a pluggable secondary junction box are designed so as to replace the voltage transformer without power outage, thereby avoiding the economic losses of users caused by the power outage, and further improving the automation level of the power system and the power supply reliability of the power system.