The invention relates to a stamping die which comprises an upper die seat (1) and a lower die seat (3). The upper die seat (1) and the lower die seat (3) are arranged oppositely. The upper die seat (1) is connected with a circular upper die (2) through a thin and long connecting rod, and the lower die seat (3) is provided with a first lower die body (5) and a second lower die body (6). The first lower die body (5) and the second lower die body (6) can form a circular cavity to be matched with the upper die to stamp a workpiece to be machined. According to the scheme, a lower die composed of the first lower die body and the second lower die body is matched with the upper die to be used for enabling the workpiece to be machined to be stamped conveniently.