PURPOSE: To easily form a head part without generating vibration and a noise, and without anneal-processing and cut-working, by pressing a rocking punch against the end part of metallic shaft parts to be worked, when forming and working the head part in the end part of the metallic shaft parts.

CONSTITUTION: In a hole 9a of a lower die 9 provided with a knock pin 11 on its bottom part, steel shaft parts 10 to be worked are inserted and set so that an end part 10a is projected. A rocking punch 7 being almost columnar and having a conical part 7a and a ring-like projecting edge part 7b on its lower surface is made to contact so that a vertex 7c is positioned on an axis 5 of the shaft parts 10, and is rock-rotated by a motor 3 of an upper punch base seat 6. The rocking punch 7 makes the vertex 7c a supporting point and is rock-rotated at an eccentric angle (θ) against the axis 5 as indicated with an arrow P, the end part 10a of the shaft parts 10 is gradually crushed in the circumferential direction, and a head part 10b is formed moderately and easily.