The invention belongs to the field of powder metallurgy manufacturing and discloses a production method for metal diffusion powder. The production method comprises the steps that cupric oxide powder with -300 meshes is selected, industrial machine oil is selected as binders, or mixed powder of reduced iron powder with -300 meshes and nickel powder with -300 meshes is selected; the cupric oxide powder and the industrial machine oil are mixed, the reduced iron powder or the mixed powder of the reduced iron powder and the nickel powder is loaded in a three-dimensional blender mixer, and then thecupric oxide powder is added into the three-dimensional blender mixer; material mixing is started, the mixed powder is added into an iron powder reducing furnace, a reducing atmosphere is added, temperature rise continues after reducing is finished, high temperature diffusion is started, a beater is utilized to scatter the powder discharged from the furnace, and then iron-copper diffusion powder or copper-iron-nickel diffusion powder with -200 meshes is screened out. The product produced by the method has the beneficial effects that ingredients are even, almost no segregation occurs, the apparent density of the product is low, and the formability is good, and has broad popularization value.