PURPOSE: To simply and inexpensively manufacture a rack and pinion steering system by forming a series of rack teeth having rectilinear pitch plane at the recess side of plastically deformed portion provided at part of a rectilinear rod blank.

CONSTITUTION: A blank W of rectilinear rod is ground on its outer peripheral surface by a grinding machine. A portion to be formed with rack teeth of a blank W is clamped at its both sides by a clamping unit 100, a pressing tool 101 is urged in contact with the axial central portion of the portion to be formed with the rack teeth, and the tool 101 is driven axially vertically of the blank W to thereby plastically deform the portion to be formed with the rack teeth to bent it in crest shape. When the plastic deformation is completed, the blank W is removed from the clamping unit 100 to thereby form a series of rack teeth having rectilinear pitch plane at the recess side of the bent portion. Thus, this steering system can be simply and inexpensively manufactured.