The utility model discloses a get device of disconnected screw tap, including electrolyte case, circulating pump, ooff valve, negative pole funnel and direct current device, direct current device's positive pole is connected in work piece and negative pole and is connected in the negative pole funnel, and electrolyte in the electrolyte case passes through circulating pump, ooff valve and the pipeline negative pole funnel that circulates, the export of negative pole funnel and work piece wait to process downthehole disconnected screw tap mutual disposition. When getting disconnected screw tap, carry electrolyte to the negative pole funnel, switch -on direct current device utilizes the disconnected screw tap and the electrolytic process between the negative pole funnel that soak in electrolyte, can be with the screw tap corruption of breaking to make disconnected screw tap size diminish, and then can conveniently will break the screw tap and take out from wait to process the hole. Clearly, the utility model discloses it takes out from wait to process the hole to utilize the electrolysis principle can conveniently will break the screw tap to can not damage the work piece.