The invention discloses a welding method and device for a ferromagnetic sputtering target material. According the welding method, through the magnetic effect of a permanent magnet chuck platform on the ferromagnetic sputtering target material, the target material, a solder and a backing plate are uniformly combined to improve the welding quality of the large-area ferromagnetic sputtering target material, so that the welded rate of the target material is high and the thickness uniformity of the target material is good. The welding method is easy to operate and has strong repeatability; the high-quality welding of the large-area ferromagnetic sputtering target material can be achieved by using a magnetic platform welding device; and the sputtering performance of the target material is significantly improved.