A Microplasma Reactor for maskless micro/nano plasma etching system based on parallel probe actuation is proposed. The microplasma reactor, having (50μm)2 or (100μm)2 inverted pyramidal hollow cathode and metal/dielectric/metal sandwich structure, is successfully fabricated here. Measurement system is set up to test the electrical and optical property of the device. Experiment results show that the device discharges stably in SF6, and the breakdown voltages of the device obey Paschen's law. V-I characteristics of the device for several gas pressures, source voltages, ballast resistors are also presented. Emission spectras of SF6 at low pressures show F atom lines, which are available for etching silicon and so on.