Abstract: An improved forming apparatus for a breaker layer to be used in a radial tire is described herein. The apparatus essentially comprises a drum device (D), a press contact device (A), first and second breaker material folding-wrapping devices (B) and (C), means for rotating said drum device (D), and means for moving said respective devices (A), (B) and (C) in the axial direction relative to said drum device (D) and for fixing them at predetermined positions. The drum device (D) includes a plurality of segments which have a width of their outer circumferential surfaces approximately equal to the width of the breaker layer to be formed, which can form a substantially cylindrical press contact surface with their outer circumferential surfaces, and which can expand and contract the diameter of said cylindrical contact surface.