PURPOSE: To bend a long size shape simultaneously, symmetrically or nonsymmetrically, in a single same operation by fixing a hollow long size shape and making a clamping head turn around a bending tool in the second direction supported on a pivot point.

CONSTITUTION: Each of the ends of a hollow long size shape 8 is clamped by a clamping head 18, and at the same time the long size shape 8 is supported in the longitudinal direction. An arbor 13 is arranged in the hollow interior. While the arbor 13 is pulled through the long size shape 8, respective clamping heads 18 are moved around bending tools 3. Bending is executed from both the ends of the long size shape 8 to the first direction of respective bending and yet symmetrically and simultaneously under the pulling at the start. The hollow long size shape is fixed while bending operation, and then the clamping head 18 is made to turn around the bending tool 3 in the second direction supported on a pivot point 25. Thus, the shape is prevented from deformation such as change in its shape, wrinkles, and bulging.