The utility model discloses an automatic grid line cleaning machine, and belongs to the field of solar cell piece processing. The automatic grid line cleaning machine comprises a machine frame, a belt, a cleaning mechanism and the like. The rotatable belt is horizontally laid on the lower portion of the machine frame and driven by a third motor arranged on one side of the machine frame, a frame vertically moving along lateral plates of the machine frame is arranged above the belt, two or more flexible bottom feet are arranged on the lower surface of the frame, and the cleaning mechanism capable of moving left and right is arranged on the frame. According to the automatic grid line cleaning machine, manual piece wiping work is converted into mechanical work by the mechanization means, and the automatic grid line cleaning machine is high in efficiency, small in piece breaking rate, simple in device structure, convenient to assemble and low in cost.