A plasma processing method includes a mounting process of mounting a holding sheet holding a substrate in a stage provided in a plasma processing apparatus, and a fixing process of fixing the holding sheet to the stage. The plasma processing method further includes a determining process of determining whether or not a contact state of the holding sheet with the stage is good or bad after the fixing process, and a plasma etching process of etching the substrate by exposing a surface of the substrate to plasma on the stage, in a case in which the contact state is determined to be good in the determining process.