The invention discloses a fertilizer agent production method which includes the steps: A adding 2-8 parts of urea, 3-9 parts of ferrous sulfate monohydrate, 4-32 parts of fenaminosulf, 2-8 parts of potassium humate, 5-12 parts of mica, 2-8 parts of urea formaldehyde, 4-5 parts of glutamic acid, 1-5 parts of magnesium nitrate, 5-9 parts of boric acid and 8-25 parts of starch into a crusher according to weight, crushing the materials, adding the crushed materials into a mixer, mixing the materials for 10-40 minutes, slowly adding the uniformly mixed materials into a melting tank, and starting a stirring device and a heating device; B pouring melted materials into a hollow triangular mold, placing calcium superphosphate balls filled with potassium chloride solution into the triangular mold, and cooling and forming the melted materials to obtain an outer shell; C cutting three vertex angles of the outer shell, forming one opening in each vertex angle, pouring ammonium sulfate solution into the outer shell from the openings, and closing the openings of the outer shell by the aid of soil balls. According to the method, seedling withering of action objects is avoided, and fertilizer waste is decreased.