According to one embodiment, a plasma processing apparatus includes a chamber being possible to maintain an atmosphere more depressurized than atmospheric pressure, a plasma generator generating a plasma inside the chamber, a gas supplier supplying a gas into the chamber, a placement part positioned below a plasma generation region and placing a processed product thereon, a depressurization part depressurizing the chamber, and a power supply electrically connected to an electrode provided on the placement part via a bus bar. The bus bar is formed of an alloy of copper and gold. Gold is more included than copper on a surface side of the bus bar. The bus bar includes a first layer formed of copper and a second layer covering the first layer and formed of an alloy of copper and gold. Gold is more included than copper on a surface side of the second layer.