There is provided a plasma processing apparatus. The apparatus comprises: a chamber body; and a power supply unit configured to output power for exciting a gas supplied to an inside of the chamber body. The power supply unit supplies, as power having a center frequency, a bandwidth, and a carrier pitch respectively corresponding to a set frequency, a set bandwidth, and a set carrier pitch that are indicated by a controller, power which is pulse-modulated so as to be a pulse frequency, a duty ratio, a high level, and a low level respectively corresponding to a set pulse frequency, a set duty ratio, a high-level set power, and a low-level set power indicated by the controller, and in which a pulse on time determined by the set pulse frequency and the set duty ratio is longer than a power fluctuation cycle of the power having the bandwidth.