It is meaningful to predict welding deformation in practical time and to apply these data in welding industry. In this paper, the inherent deformations of beading on plate welding and fillet welding are studied. A 3D thermal-elastic-plastic FEM based on interactive substructure method (ISM) is used to predict the welding deformations. Experiments are carried out to verify the computation results. Based on the computation results, the inverse analysis method is proposed to estimate the inherent deformations. Using inherent deformations, welding deformation can be accurately reproduced by elastic FEM which is much more practical and efficient. Finally, a database of inherent deformations on bead on plate welding and fillet welding including 8 different materials is developed. Meanwhile, the relationship of welding heat input and inherent deformations is discussed. The effectiveness of this method is also confirmed by experimental results.