There is provided an inductively coupled plasma processing apparatus capable of reducing a RF power loss within a high frequency power supply unit (particularly, a matching unit) and capable of enhancing a plasma generation efficiency. In this inductively coupled plasma processing apparatus, a multiple number of closed-loop secondary circuits 96, 98 independent from each other are formed between a coaxial antenna group 54 and a transformer 68. Further, by varying electrostatic capacitances of variable capacitors 64 and 66, secondary currents I2A and I2B flowing through an inner antenna 58 and an outer antenna 60, respectively, of the coaxial antenna group 54 are independently controlled. Accordingly, it is possible to readily control a plasma density distribution on a semiconductor wafer W in a diametrical direction.