In a plasma processing method, plasma processing is performed in a state where the object is attracted and held on the electrostatic chuck by applying a first voltage as an application voltage thereto and a thermal conduction gas is supplied to a gap between the electrostatic chuck and the object. The application voltage is decreased while stopping the supply of the thermal conduction gas and exhausting the thermal conduction gas remaining between the electrostatic chuck and the object upon completion of the plasma processing. The object is separated from the electrostatic chuck by setting the application voltage to the electrostatic chuck to zero after the application voltage is decreased.