Abstract: In this paper, theoretical and simulation researches on the internal and external magnetic pole etching of the anode layer Hall thruster are carried out. First, the three-dimensional particle simulation method is used to obtain the distribution of the incident ion energy and angle incident on the inner and outer magnetic poles, as well as the number of bombarding ions on the different surfaces of the inner and outer magnetic poles. It can be seen from the results that the number of bombarding ions on the upper surface of the inner magnetic pole, the inner surface of the inner magnetic pole, and the inner surface of the outer magnetic pole is larger, which is 30 times the number of bombarding ions on the other three surfaces. Next, the influence of the discharge voltage, magnetic field strength, and air pressure on the etching rate distribution of the three surfaces is analyzed in detail, and the result of the etching rate obtained is consistent with the experiment. The results of this study provide a reliable research method for evaluating the life of the thruster and reducing the etching degree of the inner and outer magnetic poles.