Disclosed is a high-frequency discharge plasma generation-based two-stage Hall-effect plasma accelerator, which comprises an annular acceleration channel having a gas inlet port, a high-frequency wave supply section, an anode, a cathode, a neutralizing electron generation portion and a magnetic-field generation element, wherein: gas introduced from the gas inlet port into the annular acceleration channel is ionized by a high-frequency wave supplied from the high-frequency wave supply section, to generate plasma; a positive ion includes in the generated plasma is accelerated by an acceleration voltage applied between the anode and cathode, and ejected outside; and an electron included in the generated plasma is restricted in its movement in the axial direction of the annular acceleration channel by an interaction with a magnetic field. The two-stage Hall-effect plasma accelerator is designed to control a degree of ion acceleration in accordance with the acceleration voltage serving as an acceleration control parameter, and control an amount of plasma generation in accordance with the high-frequency wave output serving as a plasma-generation control parameter. The two-stage Hall-effect plasma accelerator of the present invention can control the ion acceleration and the plasma generation in a highly independent manner.