The electrode temperature control device in a processing apparatus 100 includes a freezing circuit 110 comprising a compressor 148, a condenser 142, an expansion valve 150 and an evaporator 108 with the evaporator disposed inside a lower electrode 106. This electrode temperature control device does not require components such as a coolant tank for storing the coolant, a pump for supplying the coolant to the processing apparatus, a heater for adjusting the temperature of the coolant and a heat exchanger for exchanging heat between a primary coolant and a secondary coolant. Thus, the production cost can be lowered, a reduction in installation area through miniaturization of the apparatus is achieved and more efficient use of energy is achieved as well. In addition, by using CO2 as the coolant, the GWP value can be reduced to approximately {fraction (1/8000)} to {fraction (1/7000)} that of Freon.