A gate driver and a repairing method are disclosed, wherein the gate driver is provided with one or more plurality of auxiliary stages that can substitute for a disabled stage, the gate driver including a shift register provided with a plurality of first output lines; at least three output repairing lines arranged across the first output lines; at least two clock transmission lines to transmit at least two clock pulses of different phases; at least one clock repairing line arranged across the clock transmission lines; and at least one auxiliary stage connected to the output repairing lines and to the at least one clock repairing line.