A 
parallel plate type 
plasma processing apparatus including a RF feed rod for applying a 
high frequency power to a 
susceptor and a temperature detection unit for detecting the temperature of a substrate on the 
susceptor is configured to reduce an effect that 
high frequency current flowing in the RF feed rod has on temperature detection of the temperature detection unit. A surface portion of the 
susceptor serves as a mounting unit including an electrostatic chuck and a heater. A shaft, which is a protection 
pipe extracted downward from the 
processing chamber, is provided under the mounting unit. A chuck 
electrode of the electrostatic chuck serves as an 
electrode for applying a 
high frequency voltage. Provided in the shaft are two RF feed rod for supplying a power to the 
electrode and an 
optical fiber, i.e., a temperature detection unit, having a 
dielectric fluorescent material is disposed in a leading end thereof. Then, the two RF feed rods and bar type conductive leads for the heater are alternately arranged at equal intervals in a circumferential direction on a circle having the 
optical fiber at the center thereof such that the region having therein the 
optical fiber is an electromagnetic wave-free region since the 
electric force lines respectively traveling from the RF feed rods to bar type conductive leads are offset with each other.