Abstract: An electrode device for a plasma processing system is presented. The electrode device is installed in a chamber of the plasma processing system. The electrode device comprises a plurality of electrode assemblies. Each electrode assembly has at least one first electrode and at least one second electrode. The first electrode is connected to a first output of a power supply, and the second electrode, connected to a second output of the power supply. Each electrode assembly is spaced apart from each other so as to generate plasma in the chamber. The electrode assembly comprises at least two electrodes (the first electrode and the second electrode) with shorter distance between the electrodes, and the type of the power supply can be altered to increase the electric field intensity, the hollow cathode effect, plasma density and uniformity. The electrode device can raise the efficiency in processing the object, and increase the uniformity of the electric field and upgrade the quality of the object.