The invention discloses a resistance type thermal evaporation technology for preparing a ferromagnetic material Fe3Si film. The resistance type thermal evaporation technology is characterized by comprising the following steps that firstly, a high-temperature-resisting quartz plate and a single crystal silicon sheet are selected as a substrate, and cleaning and drying are conducted; secondly, iron particles and silicon particles are prepared according to different ratios; thirdly, plating materials with different ratios are obtained according to the steps, and a layer of Fe-Si mixed film is evaporated on the substrate; and fourthly, a sample obtained through the steps is put into a high-vacuum heat treatment furnace to be annealed for 2 hours at the temperature of 800-900 DEG C, and the metal-phase Fe3Si ferromagnetic film in an Fe-Si compound is obtained.