The invention discloses an electric signal acquiring method in consumable electrode arc welding, belongs to the technical field of welding, and solves the problem of influence on the voltage measurement result reliability in a welding loop by random change of the contact resistance between an electric conducting nozzle and a welding wire. Firstly, the welding wire is in contact electric connection with the electric conducting nozzle of a welding gun, and is insulated from other parts of the welding gun; the electric connecting point of the welding wire and the electric conducting nozzle of the welding gun is a voltage acquisition reference point; the electric connecting point of one welding wire is selected between an inlet of a wire feeding pipe of the welding gun and a welding wire disc as an equipotential sampling point of the voltage acquisition reference point; and then, a voltage signal acquisition amplifier is adopted to acquire voltage in the welding loop. The method is used for acquiring electric signals in the consumable electrode arc welding.