This application discloses a High-Frequency plasma processing apparatus comprising a process chamber in which a substrate to be processed is placed, a process-gas introduction line for introducing a process gas into the process chamber, a first HF electrode provided in the process chamber, a first HF power source for applying voltage to the first HF electrode, thereby generating plasma of the process gas. The apparatus further comprises a second HF electrode facing the first HF electrode in the process chamber, interposing discharge space, and a series resonator connecting the second HF electrode and the ground. The frequency of the first HF power source is not lower than 30 MHz. The series resonator is resonant as the distributed constant circuit at the frequency of the first HF power source.