The invention discloses a nail pulling mechanism of a battery liquid injection hole. The nail pulling mechanism comprises a horizontal guide rail, wherein the horizontal guide rail is arranged above ahorizontal battery transmission device and is perpendicular to a transmission direction of the horizontal battery transmission device, a horizontally-moving sliding plate is arranged on the horizontal guide plate in a sliding way, a first perpendicular guide rail is arranged on the horizontally-moving sliding plate, a first lifting sliding plate is arranged on the first perpendicular guide rail in a sliding way, a nail pulling mechanical claw is arranged on the first lifting sliding plate, a nail pulling through hole is formed in the nail pulling mechanical claw and vertically penetrates through the mechanical claw, the nail pulling through hole is connected with a plastic nail recovery box by a plastic nail recovery tube, the plastic nail recovery box is a closed box body, and the plastic nail recovery box is connected with a vacuum source via a pipeline. The nail pulling mechanism has the beneficial effects that nail pulling action only requires 1-2 seconds, and the working efficiency is obviously improved compared with the prior art; and the nail pulling mechanism is reasonable in structure and is convenient to use, and the problems of efficiency and cost of a traditional nailpulling mechanism are solved.