Abstract: The prediction of welding distortions based on the theory of inherent strain by FEM is introduced.The inherent strains are assumed to be distributed in the welds and nearby area.The relations between inherent strains and welding parameters based on some experimental curves and the thermo elastic plastic analysis can be determined.This method is more convenient because only elastic analysis is necessary.The effectiveness of the proposed method is demonstrated through the welding distortion analysis of some engineering structures as examples.