Tailor welded blanks (TWBs) include welded metal sheets, for the purpose of obtaining the desired structure of materials, decreasing product weight and increasing process flexibility and efficiency. Weld-line movement in TWBs during process is always considered as a challenging problem. Weld line movement is one of the influencing parameters, having effect on sheets formability. The subject of this study is presenting numerical model for predicting weld line movement and thickness distribution in TWBs sheet during deep drawing process. In this paper, by applying the finite element approach, ABAQUS software, a method has been developed for predicting weld line movement in TWBs. Design of experimental method (DOE) was done based on sheet thickness, radius of die, and experimental design matrix parameters has been used for obtaining weld line movement prediction model. Experimental tests were done to confirm the correctness of the simulations. Finally, the effect of punch and die radius, weld-line situation and thickness rate, on weld line movement and thickness distribution in square TWBs have been reported.