Abstract: Rotary-Gauss body heat source model can show appropriately the character of electron beam deep penetration welding, but only smooth "parabola" shape weld can be obtained. It is improved to reflect general "wine-cup" or "nail" shape weld, and also numerically simulated temperature field distributions during electron beam welding of plate by using ANSYS, and it was validated with weld profile and thermal cycle curves measured. The results of calculations is in a good agreement with the experiment.