Caulking has merits of easy manufacturing and assembly, and reduced product cost. However, though the design of the caulking process is very important in order to obtain satisfactory strength, research on caulking has been insufficient. Therefore, tensile and fatigue tests were conducted for the evaluation of the caulked part of a drum in a washing machine. The caulking process was simulated by finite element analysis, and the residual stress of the caulked part was evaluated. The residual stress of the caulked part was applied to the S-N curve of the fatigue test, and the notch effect of the caulked part was applied to the S-N curve of virgin material. As a result, the S-N curve of the caulked part can be predicted from the S-N curve of virgin materials.