A disclosed plasma processing method includes generating plasma in a chamber of a plasma processing apparatus by supplying radio frequency power from a radio frequency power source in a first period. The plasma processing method further includes stopping supply of the radio frequency power from the radio frequency power source in a second period following the first period. The plasma processing method further includes applying a negative direct-current voltage from a bias power source to a substrate support in a third period following the second period. In the third period, the radio frequency power is not supplied. In the third period, the negative direct-current voltage is set to generate ions in a chamber by secondary electrons that are emitted by causing ions in the chamber to collide with a substrate.