In the previous paper, the authors showed the method for prediction of end crack occurrence in one sided automatic welding by comparing opening displacement of the groove near the end of plate with critical displacement for crack occurrence. In the present paper, the authors tried to calculate the strain of weld center section in welding near end of the plate from opening displacement by the incremental theory of uniaxial thermally elastic plastic analysis. And they used it for prediction of end crack combining with ductility curve obtained by trans-varestraint test. As a result of these analyses, considering the nonuniformity of thickward temperature distribution in the weld center section, predicted crack location and crack length was evaluated on the three position of plate thickness and was compared to actual experimental end crack.