The invention discloses a resource utilization method of the wastewater slag of cobalt and nickel metallurgy. The method comprises the following steps of levigating a material through ball milling, then sieving, then reducing through high-pressure hydrogen to reduce nickel, cobalt, copper and the like therein into metal elements, wherein calcium, magnesium, manganese and the like are not reduced,then sorting through gravity to separating the metal elements such as nickel, cobalt and copper from other sizing agents to realize the separation of nickel, cobalt, copper and iron from other metals,then adopting magnetic separation to separate nickel, cobalt and iron from copper, smelting copper powder, then electrorefining to obtain cathode copper, then adding nickel, cobalt and iron powder inphosphoric acid to dissolve, adding hydrogen peroxide to obtain an iron phosphate precipitate, wherein nickel and cobalt are not oxidized so that the precipitation of nickel, cobalt and iron is realized, then extracting, performing reverse extraction by stages after extracting nickel and cobalt to realize the separation of nickel and cobalt, and enabling raffinate to be subjected to concentrationand crystallization to obtain an ammonium phosphate compound fertilizer. The method can be used for realizing the separation and recovery of all ingredients, the recovery rate is high, the finally obtained product has high purity, and the added value of the product is high.