PURPOSE: To improve the operating efficiency of a bending machine by distributing plural upper dies in processing order around a rotary type holder to mount them on the holder and arranging lower dies corresponding to the upper dies on a table to change each die mechanically.

CONSTITUTION: In a bending machine for pressing a work piece by upper and lower dies; a rotary type holder 1 on which plural upper dies 2, 3, 4 distributed in processing order are mounted, is horizontally mounted on the upper part of a machine body 9, and further a table 5 on which lower dies 6, 7, 8, corresponding to the upper dies 2, 3, 4 and arranged back and forth, are mounted, is mounted on the lower part of the body 9. Stillmore, the holder 1 is furnished with a driving mechanism for its desired rotation and a positioning device, and the table 5 is furnished with a back and forth displacing mechanism and a vertically moving mechanism. In this way, the die exchange is mechanically operated, and the operating efficiency of bending machine is improved.