An attempt was made to separate copper, zinc and nickel contained in plating wastewater by sulfuration treatment. Simulated plating solutions and plating wastewater from a plating industry that contained these metals at concentrations of 100 to 300 mg/dm(3) were treated with sodium sulfide (Na2S). It was found that individual precipitation of metal sulfides was achieved by selective sulfuration of mixed metal solutions of copper, zinc and nickel by controlling the pH of the solutions. In the pH range of 1.4-1.5, copper was first separated from the solution as copper sulfide. Next, zinc sulfide was formed in the pH range of 2.4-2.5. Subsequently, nickel sulfide was formed in the residual solution at pH 5.5-5.6. It was also found that copper, zinc and nickel in plating wastewater could be recovered separately as metal sulfides, in a similar way to the selective sulfuration of simulated mixed metal solutions.