The invention discloses a welding repairing process for an extrusion die. The welding repairing process comprises the following steps that firstly, failure analyzing is carried out on the abandoned die, linear cutting and observation analyzing are carried out on failure parts, and failure forms are determined; secondly, different welding repairing principles are selected for different defects; thirdly, appropriate welding methods are selected for detect forms of a working tape; fourthly, physical and chemical property analyzing is carried out on welded tissues; fifthly, machining and post-treating are carried out on welded work; and sixthly, die testing and spot actual extruding are carried out on the repaired die, the actual extruding situation of the die is explored, an extruding result is analyzed, and repairing is carried out again. According to the welding repairing process, an electric pulse low-temperature welding new technology is adopted for repairing, a solid element diffusion layer will be produced in a base surface layer, high-binding performance is shown, disengaging will not occur, the workpiece repairing efficiency is high, and after-treatment is convenient.