The invention discloses a wiring device for detecting a voltage transformer. The wiring device is characterized by comprising a low-voltage distribution box, monolithic switches, a monitoring voltmeter, wiring terminals and wires, wherein the monolithic switches are arranged in the low-voltage distribution box; three input wiring terminals of the wiring device are connected with test terminals of the detected transformer, and output wiring terminals of the wiring device are connected with sampling terminals of a transformer calibrator; two of the output wiring terminals are connected to the monitoring voltmeter, and are used for protecting the transformer calibrator from being damaged by impulse voltage when loops are switched. During the use, the monolithic switches are operated to be switched on and off to switch three different measurement loops. According to the wiring device, a plurality of transformers can be detected only by one-time boosting process, so that the detection working efficiency is greatly improved, the personnel allocation is reduced, the frequency of assembly and disassembly of high-voltage test wires is reduced, the electrification time in a high-voltage test is shortened, the safety risks in a testing process are reduced, and the safety benefits of an enterprise are improved.