The present invention relates to a waste battery treatment method which includes preparing a waste battery including a waste positive electrode which includes an aluminum current collector and a positive electrode active material layer formed on at least one surface of the aluminum current collector, heat treating the waste battery at a temperature of 650 C. or higher in an air atmosphere or oxidizing atmosphere to convert the aluminum current collector into aluminum oxide, and recovering aluminum oxide powder and positive electrode active material powder from the heat-treated waste battery.