The invention provides a novel antitheft electric meter detecting device and belongs to the technical field of electric meter overhaul tools. The novel antitheft electric meter detecting device comprises a main shaft, a fixed body, a movable body and a first measuring portion, wherein the main shaft is provided with external threads; the fixed body is in rotatable connection to one end of the mainshaft; the movable body is in threaded connection to the main shaft; the first measuring portion deflects on the movable body as the movable body rotates; the distance and the angle between the movable body and the fixed body can be measured through the threads of the main shaft and the first measuring portion, thereby calculating the length and the angle between two adjacent wiring terminals. The novel antitheft electric meter detecting device solves the technical problem that a conventional method for measuring the length and the angle between the two wiring terminals by using a caliper isnot accurate, and is inconvenient in wiring operation and cable fixation, and can quickly measure the two adjacent wiring terminals, achieves accurate measurement and facilitates wiring operation.