Abstract: The measurement of residual stress of electron beam welding need to expend great cost,so it is important to numerically simulate the value and distribution of welding residual stresses.The welding temperature field,the distributions of residual stresses of TC4 plates was simulated with a three-dimensional finite-element model(FEM).The effects of medium and high accelerated voltage on the residual stresses of electron beam welding were mainly studied.The purpose is to study the effect of vacuum electron beam welding by different processing parameter,optimize the welding parameters,and reduce the cost.The result shows that the residual stress peak value of joint welded by EBW with medium-voltage electron beam welding is higher than that of the joint with high-voltage,and its high residual stresses zone is much more concentreted on the central section of the joint.