Abstract: A plasma accelerator with closed electron drift comprising a dielectric discharge chamber (6) with internal and external annular walls (13) forming an annular accelerating channel, and a magnetic system with sources (3) of a magnetic field, a magnetic path (2), external (4) and internal (5) magnetic poles forming an operating gap in the region of the discharge chamber exit edges. An anode unit (7) with a gas distributor is located in the accelerating channel interior, and the distance from the anode-gas distributor (7) to the accelerating channel exit plane exceeds said channel width. A cathode-compensator (1) is located beyond the exit plane of the discharge chamber (6). Exit parts of the discharge chamber walls (13) facing the accelerating channel are made of conducting material. At least one dividing annular groove (12) is made on each chamber wall between its conducting and main parts.