Abstract: The treating method for a positive electrode for a non-aqueous electrolyte secondary battery is a treating method for a positive electrode for a non-aqueous electrolyte secondary battery which comprises a positive electrode having a foil containing Al and an active material which is a metal composite oxide, the method comprising: conducting a heating treatment for heating the positive electrode (heating step); melting the positive electrode using heat of reaction of the foil and the active material to obtain a molten material (melting step); and separating the molten material into a metal material containing a metal constituting the metal composite oxide and a slag (separating step). By subjecting the positive electrode to heating treatment, a reduction reaction of the positive electrode can be promoted at a low cost.