The utility model discloses a cubical switchboard transient state ground voltage sensor, including preceding TEV sensor, back TEV sensor and insulating connecting seat, preceding TEV sensor for gather the transient state ground voltage signal and the inevitable background noise signal of cubical switchboard, back TEV sensor for gather the background noise signal, insulating connecting seat links up between preceding TEV sensor and the back TEV sensor, be used for keeping apart signal interference between preceding TEV sensor and the back TEV sensor. The utility model has the advantages of simple structure, link into an integrated entity preceding TEV sensor and back TEV sensor through insulating connecting seat, like this when using, the transient state ground voltage signal and the inevitable background noise signal of cubical switchboard is gathered to the TEV sensor before the accessible, directly gather the background noise signal through back TEV sensor, carry out analysis processes with the TEV detector at last, obtain the transient state ground voltage value of cubical switchboard cabinet body surface face, realize the function of dynamic real -time analysis cubical switchboard transient state ground voltage.