Abstract: Solving the problem of ablation of track and armature is the key to the practical application of the six-pole electromagnetic launcher. One of the causes of the ablation of track and armature is the uneven distribution of current between the rails and the armature.In this paper, the finite element simulation software Ansoft Maxwell is used to simulate the three different orbits, and the distribution of the armature contact surface current density and the armature stress are obtained. The results show: the rectangular orbit maximum current density is the minimum of the three orbits; the concave-semicircle-orbit current distribution is the most uniform, and during the launch process the concave armature contact surface can effectively reduce the erosion of the rail and armature; the convex-orbit armature has the maximum stress and it can be used for high quality objects launch.