Abstract: The temperature field of electron-beam rapid prototyping is simulated by ANSYS.In this study, heat distribution is expressed as Gaussian equation.The heat loss just includes heat radiation as the process is carried out in the vacuum chamber.Temperature distributions of different scanning modes are studied and analyzed.Based on the experimental and simulation results circle scanning orderly with degressive radius from outer to inner is suitable to produce a certain width cylinder, while small electron beam current can reach temperature above the melting point.And the scanning range is consistent with the melting scope, melted powder in the depth is almost the same for the entire scanning area, so the prototyping result is uniform and the surface is flat.The temperature field of multi-layered scanning with element birth and death is predicted by simulation, and the simulation result is useful to instruct practical prototyping.