A plasma processing apparatus includes a balun having a first unbalanced terminal, a second unbalanced terminal, a first balanced terminal, and a second balanced terminal, a grounded vacuum container, a first electrode electrically connected to the first balanced terminal, and a second electrode electrically connected to the second balanced terminal. When Rp represents a resistance component between the first balanced terminal and the second balanced terminal when viewing a side of the first electrode and the second electrode from a side of the first balanced terminal and the second balanced terminal, and X represents an inductance between the first unbalanced terminal and the first balanced terminal, 1.5≤X/Rp≤5000 is satisfied.