To reduce the distortion of an adhesion, while enhancing the productivity, by easily deforming a tread member by bending and adhering it to the outer circumference of a tire molding.

The adhering surface 10H on the side of the tread member 10 which is subjected to bending deformation, when adhered to the tire molding T is slantingly notched to form grooves K1 and K2 tapering off at the end. After the tread member 10 is placed around the outer circumference of the tire molding T, the entire adhesion surface 10H is adhered to the surface of the outer circumference of the tire molding T by bendingly deforming the tread member 10 by applying pressure to the tread member 10 from the outer circumference in the direction from the inner side to the outer side across the width with rollers R. While the grooves K1 and K2 of the tread member 10 are gradually narrowed from the bottom ends to absorb the distortion of the adhesion associated with the deformation, the side of the tread member 10 is bent and deformed toward the tire molding T, air existing in the grooves K1 and K2 and between the members is eliminated, and the side of the tread member 10 is adhered along the outer circumference of the shoulder SH.