A method for repairing break of a universal connecting rod of a universal coupling includes steps of: cleaning and detecting cracks, providing primary anneal, depositing alloys, providing secondary anneal, manually milling and controlling a quality; wherein depositing the alloys includes forming gradient in an order of a bonding layer, a transition layer, a working layer and a processing layer; wherein the bonding layer: S and P in the depositing area are diluted with an FGM-KM1# material, for removing or reducing the S and P, so as to avoid cold and hot cracks; the transition layer: which is formed by an FGM-KM2# material for improving impact toughness and evacuation stress, and appropriate increasing hardness; the working layer: which is formed by an FGM-KM3# material for improving heat resistance, wear resistance and load capacity; and the processing layer: an FGM-KM4# material is used to reduce surface hardness and improve processing performance.