An electrostatic chucking method uses a substrate processing apparatus including an electrostatic chuck, a focus ring, a supply unit configured to supply a heat transfer medium to a space formed between the focus ring and the electrostatic chuck, and a plurality of electrodes provided at a region in the electrostatic chuck which corresponds to the focus ring. The electrostatic chucking method includes supplying by the supply unit the heat transfer medium to the space for a plasma processing period for which a plasma for processing the substrate is generated, and applying different voltages to the plurality of electrodes to attract and hold the focus ring on the electrostatic chuck for a period other than the plasma processing period.