The utility model discloses a detecting device of an electronic lead sealing probe sensor, which comprises a magnetic inductive circuit for detecting a magnetic element, wherein the magnetic element is fixed on a rotation shaft of a main probe; the rotation shaft of the main probe is connected with a ball valve shaft by clamping; the ball vale shaft is positioned in the space of the rotation shaft of the main probe; the magnetic inductive circuit is arranged in a circuit box of the main probe for transmitting an alarm signal when the magnetic element can not be detected; the circuit box of the main probe is further arranged in the space which is formed by an end cover and a bracket; the bracket is fixed on a flange by a lug bolt; a circuit box of an assistant probe and a bolt protection cover are tightly fixed by the lug bolt; the bolt protection cover is internally provided with the magnetic element; and the circuit box of the assistant probe transmits the alarm signal through the circuit box of the main probe when the magnetic element in the bolt protection cover can not be detected. The detecting device detects whether the ball valve shaft is illegally pulled through the main probe and detects whether a whole probe structure is illegally disassembled through the assistant probe.