A method of cleaning a stage in a plasma processing apparatus including the stage on which a substrate is placed, a lifting mechanism configured to raise and lower the substrate with respect to the stage, and a high-frequency power supply connected to the stage, includes: separating the stage and the substrate from each other using the lifting mechanism; and after the separating the stage and the substrate from each other, removing a deposit deposited on the stage with plasma generated by supplying a high-frequency power from the high-frequency power supply to the stage. In the separating the stage and the substrate from each other, a separation distance between the stage and the substrate is set such that a combined impedance formed around an outer peripheral portion of the stage is lower than a combined impedance formed immediately above a central portion of the stage.