The invention relates to a brazing method for a nickel-based alloy. According to the brazing method, novel nickel-based high-temperature brazing filler metal is utilized, reasonable vacuum brazing parameters are adopted, so that brazing of the nickel-based alloy can be realized, wherein the nickel-based high-temperature brazing filler metal BNi57NbCoWCrAlSiMo forms a solid solution through the elements in the high-temperature brazing filler metal and Ni and Cr in GH648, the wettability to a base material is good, and the brazing quality can be improved; and W and Mo are added into the brazingfiller metal so that the strength of a brazing seam can be conveniently improved, and finally the quality of the brazing seam of a brazed part can be guaranteed, the penetration rate can meet the design requirement, the shearing strength of the brazing seam can reach 500MPa or more, the reliability of the brazing seam can be greatly improved, the temperature resistance of the brazing seam can reach 1180 DEG C, and the design requirements can be met.