The utility model relates to a transformer district identification instrument which comprises a box body. A carrier communication unit, an input control interface and a data storage circuit are connected with the input end of a central processing unit. The output end of the central processing unit is connected with the carrier communication unit, the data storage circuit, the data conversion output circuit, a real-time clock, a built-in power supply charge and discharge management module, a non-volatile RAM memory unit and an extension auxiliary module. The data storage circuit is connected with an internal memory. The data conversion output circuit is connected with a display. A voltage and current conversion unit powers the units. The voltage and current conversion unit is connected with a switch control unit and an electric circuit access unit. The transformer district identification instrument provided by the utility model is mainly applied to a low voltage electric power transformer district with electric power information acquisition and loss rate abnormities, can accurately and quickly locate a fault cause, has the advantages of being safe and stable and easy operation, can quickly and accurately locate the condition of a user interface, and helps to analyze a transformer district interface.