The invention discloses an electric arc correcting device. The electric arc correcting device comprises a correcting mechanism, a walking mechanism and a control module. The correcting mechanism comprises an electric arc gun, a height control assembly and a transverse control assembly, wherein the height control assembly and the transverse control assembly are connected with the electric arc gun. The height control assembly can generate displacement in the vertical direction along with the shape of a workpiece to be corrected, and the transverse control assembly can control the transverse displacement of the electric arc gun. The walking mechanism is used for bearing the correcting mechanism. The control module is electrically connected with the correcting mechanism and the walking mechanism and used for controlling running of the correcting mechanism and the walking mechanism. The swinging speed of the electric arc correcting device is adjustable, the swinging amplitude of the electric arc correcting device is constant, the distance between the electric arc correcting device and the surface of the workpiece to be corrected is constant, and the electric arc correcting device can automatically walk. The invention further discloses an electric arc correcting system with the electric arc correcting device.