Abstract: Lap joint is one of the typical welded joints. In order to predict the welding deformation in large and complex structures,it is important to obtain the inherent deformation in lap joint. In the present study,a new inverse analysis method was proposed to obtain the inherent deformation in lap welded joints based on the combination of experimental measurement and numerical simulation. Using the inherent deformation model ob-tained by the proposed method,the welding distortion in a low carbon steel lap joint was predicted by means of forward elastic finite analysis based on the inherent strain theory. By comparing the simulated results and measured data,the prediction accuracy and effectiveness of the inverse analysis method was verified.