Hemming stamping die is a process that folds the edges of metal parts. The folded edges can improve appearance and functionality of the metal parts in various ways. For example, a smooth and safe edge can prevent injury and damage and hide sharp edges. A uniform and polished edge can enhance aesthetics and improve surface quality. A double-layered edge can protect from wear and tear and increase durability. A sealed edge can prevent moisture and dirt from entering and reduce corrosion. Hemming stamping die can also vary the height and the width of the folded edges to create different effects.